libceph: use kbasename() and kill ceph_file_part()

Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Alex Elder <elder@linaro.org>

include/linux/ceph/ceph_debug.h

@@ -3,6 +3,8 @@
 
 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
 
+#include <linux/string.h>
+
 #ifdef CONFIG_CEPH_LIB_PRETTYDEBUG
 
 /*
@@ -12,12 +14,10 @@
  */
 
 # if defined(DEBUG) || defined(CONFIG_DYNAMIC_DEBUG)
-extern const char *ceph_file_part(const char *s, int len);
 #  define dout(fmt, ...)						\
 	pr_debug("%.*s %12.12s:%-4d : " fmt,				\
 		 8 - (int)sizeof(KBUILD_MODNAME), "    ",		\
-		 ceph_file_part(__FILE__, sizeof(__FILE__)),		\
-		 __LINE__, ##__VA_ARGS__)
+		 kbasename(__FILE__), __LINE__, ##__VA_ARGS__)
 # else
 /* faux printk call just to see any compiler warnings. */
 #  define dout(fmt, ...)	do {				\