powerpc/kernel/time: Remove duplicate header

Remove linux/rtc.h which is included more than once
Signed-off-by: Brajeswar Ghosh <brajeswar.linux@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

arch/powerpc/kernel/time.c

@@ -57,7 +57,6 @@
 #include <linux/irq_work.h>
 #include <linux/clk-provider.h>
 #include <linux/suspend.h>
-#include <linux/rtc.h>
 #include <linux/sched/cputime.h>
 #include <linux/processor.h>
 #include <asm/trace.h>