ceph: remove unused and redundant variable dropping

Variable dropping is set but never read and hence is redundant
and can be removed. Cleans up clang warning:

  fs/ceph/caps.c:1170:2: warning: Value stored to 'dropping' is never read
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

fs/ceph/caps.c

@@ -1160,7 +1160,7 @@ static int __send_cap(struct ceph_mds_client *mdsc, struct ceph_cap *cap,
 	struct ceph_inode_info *ci = cap->ci;
 	struct inode *inode = &ci->vfs_inode;
 	struct cap_msg_args arg;
-	int held, revoking, dropping;
+	int held, revoking;
 	int wake = 0;
 	int delayed = 0;
 	int ret;
@@ -1168,7 +1168,6 @@ static int __send_cap(struct ceph_mds_client *mdsc, struct ceph_cap *cap,
 	held = cap->issued | cap->implemented;
 	revoking = cap->implemented & ~cap->issued;
 	retain &= ~revoking;
-	dropping = cap->issued & ~retain;
 
 	dout("__send_cap %p cap %p session %p %s -> %s (revoking %s)\n",
 	     inode, cap, cap->session,