For e.g. HZ=100, timer being 430 jiffies in the future, and 32 bit
unsigned int, there is an overflow on unsigned int right-hand side
of the expression which results with wrong values being returned.

Type cast the multiplier to 64bit to avoid that issue.

Fixes: 46c8f0b0 ("timers: Fix get_next_timer_interrupt() computation")
Signed-off-by: NMatija Glavinic Pecotic <matija.glavinic-pecotic.ext@nokia.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Reviewed-by: NAlexander Sverdlin <alexander.sverdlin@nokia.com>
Cc: khilman@baylibre.com
Cc: akpm@linux-foundation.org
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/a7900f04-2a21-c9fd-67be-ab334d459ee5@nokia.com