nfsd: simplify test_bit return in NFSD_FILE_KEY_FULL comparator

test_bit returns bool, so we can just compare the result of that to the
key->gc value without the "!!".

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

Author: jtlayton

fs/nfsd/filecache.c

@@ -189,7 +189,7 @@ static int nfsd_file_obj_cmpfn(struct rhashtable_compare_arg *arg,
 			return 1;
 		if (!nfsd_match_cred(nf->nf_cred, key->cred))
 			return 1;
-		if (!!test_bit(NFSD_FILE_GC, &nf->nf_flags) != key->gc)
+		if (test_bit(NFSD_FILE_GC, &nf->nf_flags) != key->gc)
 			return 1;
 		if (test_bit(NFSD_FILE_HASHED, &nf->nf_flags) == 0)
 			return 1;