ceph: make logical calculation functions return bool

This patch makes serverl logical caculation functions return bool to
improve readability due to these particular functions only using 0/1
as their return value.

No functional change.

Signed-off-by: Zhang Zhuoyu <zhangzhuoyu@cmss.chinamobile.com>

include/linux/ceph/decode.h

@@ -47,7 +47,7 @@ static inline void ceph_decode_copy(void **p, void *pv, size_t n)
 /*
  * bounds check input.
  */
-static inline int ceph_has_room(void **p, void *end, size_t n)
+static inline bool ceph_has_room(void **p, void *end, size_t n)
 {
 	return end >= *p && n <= end - *p;
 }