ceph: remove unused variables in ceph_mdsmap_decode()

Fix build warnings:

  fs/ceph/mdsmap.c: In function ‘ceph_mdsmap_decode’:
  fs/ceph/mdsmap.c:192:7: warning: variable ‘info_cv’ set but not used [-Wunused-but-set-variable]
  fs/ceph/mdsmap.c:177:7: warning: variable ‘state_seq’ set but not used [-Wunused-but-set-variable]
  fs/ceph/mdsmap.c:123:15: warning: variable ‘mdsmap_cv’ set but not used [-Wunused-but-set-variable]

Note that p is increased in ceph_decode_*.
Signed-off-by: Jia Yang <jiayang5@huawei.com>
Reviewed-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

fs/ceph/mdsmap.c

@@ -120,7 +120,7 @@ struct ceph_mdsmap *ceph_mdsmap_decode(void **p, void *end)
 	const void *start = *p;
 	int i, j, n;
 	int err;
-	u8 mdsmap_v, mdsmap_cv;
+	u8 mdsmap_v;
 	u16 mdsmap_ev;
 
 	m = kzalloc(sizeof(*m), GFP_NOFS);
@@ -129,7 +129,7 @@ struct ceph_mdsmap *ceph_mdsmap_decode(void **p, void *end)
 
 	ceph_decode_need(p, end, 1 + 1, bad);
 	mdsmap_v = ceph_decode_8(p);
-	mdsmap_cv = ceph_decode_8(p);
+	*p += sizeof(u8);			/* mdsmap_cv */
 	if (mdsmap_v >= 4) {
 	       u32 mdsmap_len;
 	       ceph_decode_32_safe(p, end, mdsmap_len, bad);
@@ -174,7 +174,6 @@ struct ceph_mdsmap *ceph_mdsmap_decode(void **p, void *end)
 		u64 global_id;
 		u32 namelen;
 		s32 mds, inc, state;
-		u64 state_seq;
 		u8 info_v;
 		void *info_end = NULL;
 		struct ceph_entity_addr addr;
@@ -189,9 +188,8 @@ struct ceph_mdsmap *ceph_mdsmap_decode(void **p, void *end)
 		info_v= ceph_decode_8(p);
 		if (info_v >= 4) {
 			u32 info_len;
-			u8 info_cv;
 			ceph_decode_need(p, end, 1 + sizeof(u32), bad);
-			info_cv = ceph_decode_8(p);
+			*p += sizeof(u8);	/* info_cv */
 			info_len = ceph_decode_32(p);
 			info_end = *p + info_len;
 			if (info_end > end)
@@ -210,7 +208,7 @@ struct ceph_mdsmap *ceph_mdsmap_decode(void **p, void *end)
 		mds = ceph_decode_32(p);
 		inc = ceph_decode_32(p);
 		state = ceph_decode_32(p);
-		state_seq = ceph_decode_64(p);
+		*p += sizeof(u64);		/* state_seq */
 		err = ceph_decode_entity_addr(p, end, &addr);
 		if (err)
 			goto corrupt;