ceph: fix fall-through warnings for Clang

In preparation to enable -Wimplicit-fallthrough for Clang, fix a couple
of warnings by explicitly adding a break and a goto statements instead
of just letting the code fall through to the next case.

URL: https://github.com/KSPP/linux/issues/115
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Reviewed-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

fs/ceph/dir.c

@@ -631,10 +631,12 @@ static loff_t ceph_dir_llseek(struct file *file, loff_t offset, int whence)
 	switch (whence) {
 	case SEEK_CUR:
 		offset += file->f_pos;
+		break;
 	case SEEK_SET:
 		break;
 	case SEEK_END:
 		retval = -EOPNOTSUPP;
+		goto out;
 	default:
 		goto out;
 	}