Fix tls_prf generic dependencies

One version was already surrounded by the USE_PSA define,
so the VIA_XX_OR_XX macros were removed;
Second version is when USE_PSA is undefined, so MBEDTLS_
macros can be used. 
Signed-off-by: Andrzej Kurek <andrzej.kurek@arm.com>
diff --git a/library/ssl_tls.c b/library/ssl_tls.c
index 4678f53..c8904f2 100644
--- a/library/ssl_tls.c
+++ b/library/ssl_tls.c
@@ -5447,8 +5447,8 @@
     return( PSA_SUCCESS );
 }
 
-#if defined(MBEDTLS_HAS_ALG_SHA_384_VIA_MD_OR_PSA_BASED_ON_USE_PSA) || \
-    defined(MBEDTLS_HAS_ALG_SHA_256_VIA_MD_OR_PSA_BASED_ON_USE_PSA)
+#if defined(PSA_WANT_ALG_SHA_384) || \
+    defined(PSA_WANT_ALG_SHA_256)
 MBEDTLS_CHECK_RETURN_CRITICAL
 static int tls_prf_generic( mbedtls_md_type_t md_type,
                             const unsigned char *secret, size_t slen,
@@ -5523,9 +5523,12 @@
 
     return( 0 );
 }
-#endif
+#endif /* PSA_WANT_ALG_SHA_256 || PSA_WANT_ALG_SHA_384 */
 #else /* MBEDTLS_USE_PSA_CRYPTO */
 
+#if defined(MBEDTLS_MD_C) &&       \
+    ( defined(MBEDTLS_SHA256_C) || \
+      defined(MBEDTLS_SHA384_C) )
 MBEDTLS_CHECK_RETURN_CRITICAL
 static int tls_prf_generic( mbedtls_md_type_t md_type,
                             const unsigned char *secret, size_t slen,
@@ -5616,6 +5619,7 @@
 
     return( ret );
 }
+#endif /* MBEDTLS_MD_C && ( MBEDTLS_SHA256_C || MBEDTLS_SHA384_C ) */
 #endif /* MBEDTLS_USE_PSA_CRYPTO */
 
 #if defined(MBEDTLS_HAS_ALG_SHA_256_VIA_MD_OR_PSA_BASED_ON_USE_PSA)