Replace MBEDTLS_MD_CAN_SHA224 with PSA_WANT_ALG_SHA_224

Signed-off-by: Elena Uziunaite <elena.uziunaite@arm.com>
diff --git a/programs/ssl/ssl_test_common_source.c b/programs/ssl/ssl_test_common_source.c
index 1ff2077..ca0ce30 100644
--- a/programs/ssl/ssl_test_common_source.c
+++ b/programs/ssl/ssl_test_common_source.c
@@ -301,7 +301,7 @@
 #if defined(MBEDTLS_MD_CAN_SHA256)
     MBEDTLS_SSL_SIG_ALG(MBEDTLS_SSL_HASH_SHA256)
 #endif
-#if defined(MBEDTLS_MD_CAN_SHA224)
+#if defined(PSA_WANT_ALG_SHA_224)
     MBEDTLS_SSL_SIG_ALG(MBEDTLS_SSL_HASH_SHA224)
 #endif
 #if defined(MBEDTLS_RSA_C) && defined(MBEDTLS_MD_CAN_SHA256)