Revert commit 33af72df in order to not depend on test code

Signed-off-by: Michael Schuster <michael@schuster.ms>
diff --git a/programs/cipher/cipher_aead_demo.c b/programs/cipher/cipher_aead_demo.c
index 60a5ea2..853ec20 100644
--- a/programs/cipher/cipher_aead_demo.c
+++ b/programs/cipher/cipher_aead_demo.c
@@ -35,8 +35,6 @@
 
 #include "mbedtls/cipher.h"
 
-#include <test/helpers.h>
-
 #include <stdlib.h>
 #include <stdio.h>
 #include <string.h>
@@ -80,6 +78,16 @@
  * 32-byte is enough to all the key size supported by this program. */
 const unsigned char key_bytes[32] = { 0x2a };
 
+/* Print the contents of a buffer in hex */
+void print_buf(const char *title, unsigned char *buf, size_t len)
+{
+    printf("%s:", title);
+    for (size_t i = 0; i < len; i++) {
+        printf(" %02x", buf[i]);
+    }
+    printf("\n");
+}
+
 /* Run an Mbed TLS function and bail out if it fails.
  * A string description of the error code can be recovered with:
  * programs/util/strerror <value> */
@@ -190,7 +198,7 @@
     p += tag_len;
 
     olen = p - out;
-    mbedtls_test_print_buf("out", out, olen);
+    print_buf("out", out, olen);
 
 exit:
     return ret;
diff --git a/programs/hash/md_hmac_demo.c b/programs/hash/md_hmac_demo.c
index ba51bfd..4b5aa3b 100644
--- a/programs/hash/md_hmac_demo.c
+++ b/programs/hash/md_hmac_demo.c
@@ -32,8 +32,6 @@
 
 #include "mbedtls/platform_util.h" // for mbedtls_platform_zeroize
 
-#include <test/helpers.h>
-
 #include <stdlib.h>
 #include <stdio.h>
 
@@ -58,6 +56,16 @@
  * This example program uses SHA-256, so a 32-byte key makes sense. */
 const unsigned char key_bytes[32] = { 0 };
 
+/* Print the contents of a buffer in hex */
+void print_buf(const char *title, unsigned char *buf, size_t len)
+{
+    printf("%s:", title);
+    for (size_t i = 0; i < len; i++) {
+        printf(" %02x", buf[i]);
+    }
+    printf("\n");
+}
+
 /* Run an Mbed TLS function and bail out if it fails.
  * A string description of the error code can be recovered with:
  * programs/util/strerror <value> */
@@ -99,14 +107,14 @@
     CHK(mbedtls_md_hmac_update(&ctx, msg1_part1, sizeof(msg1_part1)));
     CHK(mbedtls_md_hmac_update(&ctx, msg1_part2, sizeof(msg1_part2)));
     CHK(mbedtls_md_hmac_finish(&ctx, out));
-    mbedtls_test_print_buf("msg1", out, mbedtls_md_get_size(info));
+    print_buf("msg1", out, mbedtls_md_get_size(info));
 
     /* compute HMAC(key, msg2_part1 | msg2_part2) */
     CHK(mbedtls_md_hmac_reset(&ctx));     // prepare for new operation
     CHK(mbedtls_md_hmac_update(&ctx, msg2_part1, sizeof(msg2_part1)));
     CHK(mbedtls_md_hmac_update(&ctx, msg2_part2, sizeof(msg2_part2)));
     CHK(mbedtls_md_hmac_finish(&ctx, out));
-    mbedtls_test_print_buf("msg2", out, mbedtls_md_get_size(info));
+    print_buf("msg2", out, mbedtls_md_get_size(info));
 
 exit:
     mbedtls_md_free(&ctx);
diff --git a/programs/psa/aead_demo.c b/programs/psa/aead_demo.c
index b300e36..619166d 100644
--- a/programs/psa/aead_demo.c
+++ b/programs/psa/aead_demo.c
@@ -36,8 +36,6 @@
 
 #include "psa/crypto.h"
 
-#include <test/helpers.h>
-
 #include <stdlib.h>
 #include <stdio.h>
 #include <string.h>
@@ -83,6 +81,16 @@
  * 32-byte is enough to all the key size supported by this program. */
 const unsigned char key_bytes[32] = { 0x2a };
 
+/* Print the contents of a buffer in hex */
+void print_buf(const char *title, uint8_t *buf, size_t len)
+{
+    printf("%s:", title);
+    for (size_t i = 0; i < len; i++) {
+        printf(" %02x", buf[i]);
+    }
+    printf("\n");
+}
+
 /* Run a PSA function and bail out if it fails.
  * The symbolic name of the error code can be recovered using:
  * programs/psa/psa_constant_name status <value> */
@@ -208,7 +216,7 @@
     p += olen_tag;
 
     olen = p - out;
-    mbedtls_test_print_buf("out", out, olen);
+    print_buf("out", out, olen);
 
 exit:
     psa_aead_abort(&op);   // required on errors, harmless on success
diff --git a/programs/psa/hmac_demo.c b/programs/psa/hmac_demo.c
index a85de00..f44f9a7 100644
--- a/programs/psa/hmac_demo.c
+++ b/programs/psa/hmac_demo.c
@@ -32,8 +32,6 @@
 
 #include "mbedtls/platform_util.h" // for mbedtls_platform_zeroize
 
-#include <test/helpers.h>
-
 #include <stdlib.h>
 #include <stdio.h>
 
@@ -60,6 +58,16 @@
  * This example program uses SHA-256, so a 32-byte key makes sense. */
 const unsigned char key_bytes[32] = { 0 };
 
+/* Print the contents of a buffer in hex */
+void print_buf(const char *title, uint8_t *buf, size_t len)
+{
+    printf("%s:", title);
+    for (size_t i = 0; i < len; i++) {
+        printf(" %02x", buf[i]);
+    }
+    printf("\n");
+}
+
 /* Run a PSA function and bail out if it fails.
  * The symbolic name of the error code can be recovered using:
  * programs/psa/psa_constant_name status <value> */
@@ -114,14 +122,14 @@
     PSA_CHECK(psa_mac_update(&op, msg1_part1, sizeof(msg1_part1)));
     PSA_CHECK(psa_mac_update(&op, msg1_part2, sizeof(msg1_part2)));
     PSA_CHECK(psa_mac_sign_finish(&op, out, sizeof(out), &out_len));
-    mbedtls_test_print_buf("msg1", out, out_len);
+    print_buf("msg1", out, out_len);
 
     /* compute HMAC(key, msg2_part1 | msg2_part2) */
     PSA_CHECK(psa_mac_sign_setup(&op, key, alg));
     PSA_CHECK(psa_mac_update(&op, msg2_part1, sizeof(msg2_part1)));
     PSA_CHECK(psa_mac_update(&op, msg2_part2, sizeof(msg2_part2)));
     PSA_CHECK(psa_mac_sign_finish(&op, out, sizeof(out), &out_len));
-    mbedtls_test_print_buf("msg2", out, out_len);
+    print_buf("msg2", out, out_len);
 
 exit:
     psa_mac_abort(&op);   // needed on error, harmless on success
diff --git a/tests/include/test/helpers.h b/tests/include/test/helpers.h
index 10b321d..d08100f 100644
--- a/tests/include/test/helpers.h
+++ b/tests/include/test/helpers.h
@@ -381,9 +381,6 @@
 int mbedtls_test_hexcmp(uint8_t *a, uint8_t *b,
                         uint32_t a_len, uint32_t b_len);
 
-/* Print the contents of a buffer in hex */
-void mbedtls_test_print_buf(const char *title, unsigned char *buf, size_t len);
-
 #if defined(MBEDTLS_PSA_CRYPTO_C) && defined(MBEDTLS_PSA_CRYPTO_EXTERNAL_RNG)
 #include "test/fake_external_rng_for_test.h"
 #endif
diff --git a/tests/src/helpers.c b/tests/src/helpers.c
index 29b2df5..065d17d 100644
--- a/tests/src/helpers.c
+++ b/tests/src/helpers.c
@@ -660,15 +660,6 @@
     return ret;
 }
 
-void mbedtls_test_print_buf(const char *title, unsigned char *buf, size_t len)
-{
-    printf("%s:", title);
-    for (size_t i = 0; i < len; i++) {
-        printf(" %02x", buf[i]);
-    }
-    printf("\n");
-}
-
 #if defined(MBEDTLS_TEST_HOOKS)
 void mbedtls_test_err_add_check(int high, int low,
                                 const char *file, int line)