kfifo: kfifo_is_{full,empty} should return bools, not ints

For consistency with other kfifo routines, return bool, not int.
Signed-off-by: Robert P. J. Day <rpjday@crashcourse.ca>
Cc: Stefani Seibold <stefani@seibold.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

include/linux/kfifo.h

@@ -171,7 +171,7 @@ static inline unsigned int kfifo_len(struct kfifo *fifo)
  * kfifo_is_empty - returns true if the fifo is empty
  * @fifo: the fifo to be used.
  */
-static inline __must_check int kfifo_is_empty(struct kfifo *fifo)
+static inline __must_check bool kfifo_is_empty(struct kfifo *fifo)
 {
 	return fifo->in == fifo->out;
 }
@@ -180,7 +180,7 @@ static inline __must_check int kfifo_is_empty(struct kfifo *fifo)
  * kfifo_is_full - returns true if the fifo is full
  * @fifo: the fifo to be used.
  */
-static inline __must_check int kfifo_is_full(struct kfifo *fifo)
+static inline __must_check bool kfifo_is_full(struct kfifo *fifo)
 {
 	return kfifo_len(fifo) == kfifo_size(fifo);
 }