Disallow ASN.1 enumerated types to be treated as strings.

They are actually integers.

Problem reported by: Scott McPeak <scott.g.mcpeak@gmail.com>
Reviewed-by: NTomas Mraz <tomas@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/14774)

crypto/asn1/tasn_dec.c

@@ -66,7 +66,7 @@ static const unsigned long tag2bit[32] = {
     /* tags  4- 7 */
     B_ASN1_OCTET_STRING, 0, 0, B_ASN1_UNKNOWN,
     /* tags  8-11 */
-    B_ASN1_UNKNOWN, B_ASN1_UNKNOWN, B_ASN1_UNKNOWN, B_ASN1_UNKNOWN,
+    B_ASN1_UNKNOWN, B_ASN1_UNKNOWN, 0, B_ASN1_UNKNOWN,
     /* tags 12-15 */
     B_ASN1_UTF8STRING, B_ASN1_UNKNOWN, B_ASN1_UNKNOWN, B_ASN1_UNKNOWN,
     /* tags 16-19 */