Fix MD_PSA_INIT called before initializing some data structures

This fixes accesses to uninitialized memory in test code if
`psa_crypto_init()` fails.

A lot of those were pointed out by Coverity. I quickly reviewed all calls to
`MD_PSA_INIT()` manually, rather than follow any particular list.

Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
diff --git a/tests/suites/test_suite_ecdsa.function b/tests/suites/test_suite_ecdsa.function
index f16a6d4..d9ff802 100644
--- a/tests/suites/test_suite_ecdsa.function
+++ b/tests/suites/test_suite_ecdsa.function
@@ -196,13 +196,12 @@
 {
     mbedtls_ecp_group grp;
     mbedtls_mpi d, r, s, r_check, s_check;
-
-    MD_PSA_INIT();
-
     mbedtls_ecp_group_init(&grp);
     mbedtls_mpi_init(&d); mbedtls_mpi_init(&r); mbedtls_mpi_init(&s);
     mbedtls_mpi_init(&r_check); mbedtls_mpi_init(&s_check);
 
+    MD_PSA_INIT();
+
     TEST_ASSERT(mbedtls_ecp_group_load(&grp, id) == 0);
     TEST_ASSERT(mbedtls_test_read_mpi(&d, d_str) == 0);
     TEST_ASSERT(mbedtls_test_read_mpi(&r_check, r_str) == 0);
@@ -235,13 +234,13 @@
     unsigned char sig[200];
     size_t sig_len, i;
 
-    MD_PSA_INIT();
-
     mbedtls_ecdsa_init(&ctx);
     memset(&rnd_info, 0x00, sizeof(mbedtls_test_rnd_pseudo_info));
     memset(hash, 0, sizeof(hash));
     memset(sig, 0x2a, sizeof(sig));
 
+    MD_PSA_INIT();
+
     /* generate signing key */
     TEST_ASSERT(mbedtls_ecdsa_genkey(&ctx, id,
                                      &mbedtls_test_rnd_pseudo_rand,
@@ -300,13 +299,13 @@
     unsigned char sig[200];
     size_t sig_len, i;
 
-    MD_PSA_INIT();
-
     mbedtls_ecdsa_init(&ctx);
     memset(&rnd_info, 0x00, sizeof(mbedtls_test_rnd_pseudo_info));
     memset(hash, 0, sizeof(hash));
     memset(sig, 0x2a, sizeof(sig));
 
+    MD_PSA_INIT();
+
     /* prepare material for signature */
     TEST_ASSERT(mbedtls_test_rnd_pseudo_rand(&rnd_info,
                                              hash, sizeof(hash)) == 0);
@@ -436,12 +435,12 @@
     unsigned char sig[MBEDTLS_ECDSA_MAX_LEN];
     size_t slen;
 
-    MD_PSA_INIT();
-
     mbedtls_ecdsa_restart_init(&rs_ctx);
     mbedtls_ecdsa_init(&ctx);
     memset(sig, 0, sizeof(sig));
 
+    MD_PSA_INIT();
+
     TEST_ASSERT(mbedtls_ecp_group_load(&ctx.grp, id) == 0);
     TEST_ASSERT(mbedtls_test_read_mpi(&ctx.d, d_str) == 0);