add reset_unknow() in enc.c to resolve 'enc: Multiple cipher or unknown options' (#24)

Reviewed-on: http://13.234.246.121:3000/Neominds/ossl35vx69/pulls/24
Co-authored-by: siddhant <siddhant.singh@neominds.in>
Co-committed-by: siddhant <siddhant.singh@neominds.in>

vxworks-6.9/target/src/openssl/OPENSSL/openssl-3.5.0/apps/enc.c

@@ -159,6 +159,8 @@ int enc_main(int argc, char **argv)
     EVP_SKEY *skey = NULL;
     EVP_SKEYMGMT *mgmt = NULL;
 	
+	reset_unknown();
+
     /* first check the command name */
     if (strcmp(argv[0], "base64") == 0)
         base64 = 1;