Fix memory leak in cmp_calc_protection()
Triggered by a  memory allocation failure.
Detected by PR
@@ -91,7 +91,7 @@ ASN1_BIT_STRING *ossl_cmp_calc_protection(const OSSL_CMP_CTX *ctx,
goto end;
if ((prot = ASN1_BIT_STRING_new()) == NULL)
- return NULL;
+ goto end;
/* OpenSSL defaults all bit strings to be encoded as ASN.1 NamedBitList */
prot->flags &= ~(ASN1_STRING_FLAG_BITS_LEFT | 0x07);
prot->flags |= ASN1_STRING_FLAG_BITS_LEFT;
