timekeeping: Remove __current_kernel_time()

The __current_kernel_time() function based on 'struct timespec' is no
longer recommended for new code, and the only user of this function has
been replaced by commit 6909e29f ("kdb: use __ktime_get_real_seconds
instead of __current_kernel_time").

Remove the obsolete interface.
Signed-off-by: Baolin Wang <baolin.wang@linaro.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: arnd@arndb.de
Cc: sboyd@kernel.org
Cc: broonie@kernel.org
Cc: john.stultz@linaro.org
Link: https://lkml.kernel.org/r/1a9dbea7ee2cda7efe9ed330874075cf17fdbff6.1523596316.git.baolin.wang@linaro.org

include/linux/timekeeping32.h

@@ -9,9 +9,6 @@
 extern void do_gettimeofday(struct timeval *tv);
 unsigned long get_seconds(void);
 
-/* does not take xtime_lock */
-struct timespec __current_kernel_time(void);
-
 static inline struct timespec current_kernel_time(void)
 {
 	struct timespec64 now = current_kernel_time64();

kernel/time/timekeeping.c

@@ -2139,13 +2139,6 @@ unsigned long get_seconds(void)
 }
 EXPORT_SYMBOL(get_seconds);
 
-struct timespec __current_kernel_time(void)
-{
-	struct timekeeper *tk = &tk_core.timekeeper;
-
-	return timespec64_to_timespec(tk_xtime(tk));
-}
-
 struct timespec64 current_kernel_time64(void)
 {
 	struct timekeeper *tk = &tk_core.timekeeper;