nfsd: safer handling of corrupted c_type

This can only happen if there's a bug somewhere, so let's make it a WARN
not a printk.  Also, I think it's safest to ignore the corruption rather
than trying to fix it by removing a cache entry.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

fs/nfsd/nfscache.c

@@ -477,8 +477,7 @@ int nfsd_cache_lookup(struct svc_rqst *rqstp)
 		rtn = RC_REPLY;
 		break;
 	default:
-		printk(KERN_WARNING "nfsd: bad repcache type %d\n", rp->c_type);
-		nfsd_reply_cache_free_locked(b, rp, nn);
+		WARN_ONCE(1, "nfsd: bad repcache type %d\n", rp->c_type);
 	}
 
 out_trace: