x86: Fix S4 regression

Commit 4b239f45

 ("x86-64, mm: Put early page table high") causes a S4
regression since 2.6.39, namely the machine reboots occasionally at S4
resume.  It doesn't happen always, overall rate is about 1/20.  But,
like other bugs, once when this happens, it continues to happen.

This patch fixes the problem by essentially reverting the memory
assignment in the older way.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
Cc: <stable@kernel.org>
Cc: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Yinghai Lu <yinghai.lu@oracle.com>
[ We'll hopefully find the real fix, but that's too late for 3.1 now ]
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>