[PATCH] remove special HPET_EMULATE_RTC config option

We had a user whose apps weren't working correctly because his "rtc" wasn't
working fully.

For the sake of simplicity, it seems sensible to always enable HPET RTC
emulation.

Remove a special config option for HPET_EMULATE_RTC and make it directly
depend on HPET_TIMER and RTC. This will avoid the hangs when EMULATE_RTC
is not configured and when some userlevel script depends on RTC interrupt,
as in:

http://bugzilla.kernel.org/show_bug.cgi?id=4904

Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>