Remove preprocessor directive for consistency

Other cases in this switch statement aren't guarded either.
diff --git a/library/psa_crypto.c b/library/psa_crypto.c
index cb7b5cf..154806a 100644
--- a/library/psa_crypto.c
+++ b/library/psa_crypto.c
@@ -2529,10 +2529,8 @@
             return( 64 );
         case PSA_ALG_SHA_256:
             return( 64 );
-#if !defined(MBEDTLS_SHA512_NO_SHA384)
         case PSA_ALG_SHA_384:
             return( 128 );
-#endif
         case PSA_ALG_SHA_512:
             return( 128 );
         default: