Rename psa_helpers.function to psa_crypto_helpers.h

This file isn't like the other .function files: it isn't concatenated
by a separate preprocessing script, but included via C preprocessing.

Rename this file to .h. This isn't a normal C header, because it
defines auxiliary functions. But the functions aren't big and we only
have one compilation unit per executable, so this is good enough for
what we're doing.
diff --git a/tests/Makefile b/tests/Makefile
index bc88e82..e2a32a1 100644
--- a/tests/Makefile
+++ b/tests/Makefile
@@ -104,7 +104,7 @@
 	echo "  CC    $<"
 	$(CC) $(LOCAL_CFLAGS) $(CFLAGS) $<	$(LOCAL_LDFLAGS) $(LDFLAGS) -o $@
 
-$(filter test_suite_psa_crypto%, $(BINARIES)): psa_helpers.function
+$(filter test_suite_psa_crypto%, $(BINARIES)): psa_crypto_helpers.h
 
 clean:
 ifndef WINDOWS
diff --git a/tests/psa_helpers.function b/tests/psa_crypto_helpers.h
similarity index 96%
rename from tests/psa_helpers.function
rename to tests/psa_crypto_helpers.h
index edaea80..b1c5968 100644
--- a/tests/psa_helpers.function
+++ b/tests/psa_crypto_helpers.h
@@ -19,6 +19,9 @@
  *  This file is part of mbed TLS (https://tls.mbed.org)
  */
 
+#ifndef PSA_CRYPTO_HELPERS_H
+#define PSA_CRYPTO_HELPERS_H
+
 #if defined(MBEDTLS_PSA_CRYPTO_SPM)
 #include "spm/psa_defs.h"
 #endif
@@ -78,8 +81,4 @@
  */
 #define PSA_DONE( ) test_helper_psa_done( __LINE__, __FILE__ )
 
-/*
- * Local Variables:
- * mode: c
- * End:
- */
+#endif /* PSA_CRYPTO_HELPERS_H */
diff --git a/tests/suites/test_suite_pk.function b/tests/suites/test_suite_pk.function
index 0e02c3e..3d38535 100644
--- a/tests/suites/test_suite_pk.function
+++ b/tests/suites/test_suite_pk.function
@@ -12,7 +12,7 @@
 
 #if defined(MBEDTLS_USE_PSA_CRYPTO)
 #include "mbedtls/psa_util.h"
-#include "psa_helpers.function"
+#include "psa_crypto_helpers.h"
 #endif
 
 static int rnd_std_rand( void *rng_state, unsigned char *output, size_t len );
diff --git a/tests/suites/test_suite_psa_crypto.function b/tests/suites/test_suite_psa_crypto.function
index cb64532..4441e9b 100644
--- a/tests/suites/test_suite_psa_crypto.function
+++ b/tests/suites/test_suite_psa_crypto.function
@@ -5,7 +5,7 @@
 #include "mbedtls/asn1write.h"
 #include "mbedtls/oid.h"
 
-#include "psa_helpers.function"
+#include "psa_crypto_helpers.h"
 
 /** An invalid export length that will never be set by psa_export_key(). */
 static const size_t INVALID_EXPORT_LENGTH = ~0U;
diff --git a/tests/suites/test_suite_psa_crypto_entropy.function b/tests/suites/test_suite_psa_crypto_entropy.function
index cd1b81f..8538d6d 100644
--- a/tests/suites/test_suite_psa_crypto_entropy.function
+++ b/tests/suites/test_suite_psa_crypto_entropy.function
@@ -4,7 +4,7 @@
 #include "mbedtls/entropy.h"
 #include "mbedtls/entropy_poll.h"
 
-#include "psa_helpers.function"
+#include "psa_crypto_helpers.h"
 #if defined(MBEDTLS_PSA_ITS_FILE_C)
 #include <stdio.h>
 #else
diff --git a/tests/suites/test_suite_psa_crypto_hash.function b/tests/suites/test_suite_psa_crypto_hash.function
index e15f335..d50ff5a 100644
--- a/tests/suites/test_suite_psa_crypto_hash.function
+++ b/tests/suites/test_suite_psa_crypto_hash.function
@@ -2,7 +2,7 @@
 
 #include <stdint.h>
 
-#include "psa_helpers.function"
+#include "psa_crypto_helpers.h"
 
 /* END_HEADER */
 
diff --git a/tests/suites/test_suite_psa_crypto_init.function b/tests/suites/test_suite_psa_crypto_init.function
index eaf1b8b..3c4b42e 100644
--- a/tests/suites/test_suite_psa_crypto_init.function
+++ b/tests/suites/test_suite_psa_crypto_init.function
@@ -1,7 +1,7 @@
 /* BEGIN_HEADER */
 #include <stdint.h>
 
-#include "psa_helpers.function"
+#include "psa_crypto_helpers.h"
 /* Some tests in this module configure entropy sources. */
 #include "psa_crypto_invasive.h"
 
diff --git a/tests/suites/test_suite_psa_crypto_persistent_key.function b/tests/suites/test_suite_psa_crypto_persistent_key.function
index 53f6cb8..fc19248 100644
--- a/tests/suites/test_suite_psa_crypto_persistent_key.function
+++ b/tests/suites/test_suite_psa_crypto_persistent_key.function
@@ -1,7 +1,7 @@
 /* BEGIN_HEADER */
 #include <stdint.h>
 
-#include "psa_helpers.function"
+#include "psa_crypto_helpers.h"
 #include "psa_crypto_storage.h"
 
 #include "mbedtls/md.h"
diff --git a/tests/suites/test_suite_psa_crypto_slot_management.function b/tests/suites/test_suite_psa_crypto_slot_management.function
index da93bc8..3b9eada 100644
--- a/tests/suites/test_suite_psa_crypto_slot_management.function
+++ b/tests/suites/test_suite_psa_crypto_slot_management.function
@@ -1,7 +1,7 @@
 /* BEGIN_HEADER */
 #include <stdint.h>
 
-#include "psa_helpers.function"
+#include "psa_crypto_helpers.h"
 #include "psa_crypto_storage.h"
 
 typedef enum