hrtimer: Remove unused header include

seq_file.h does not need to be included, so remove it.
Signed-off-by: Yangtao Li <tiny.windzz@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20190607174253.27403-1-tiny.windzz@gmail.com

kernel/time/hrtimer.c

@@ -30,7 +30,6 @@
 #include <linux/syscalls.h>
 #include <linux/interrupt.h>
 #include <linux/tick.h>
-#include <linux/seq_file.h>
 #include <linux/err.h>
 #include <linux/debugobjects.h>
 #include <linux/sched/signal.h>