[PATCH] Add suspend/resume for HPET

This adds support of suspend/resume on i386 for HPET, which fixes a
number of timer-related failures around STR.

Signed-off-by: Maxim Levitsky <maximlevitsky@gmail.com>
Acked-by: Michael S. Tsirkin <mst@dev.mellanox.co.il>
Acked-by: Jeff Chua <jeff.chua.linux@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>