x86: Move bios page reserve early to head32/64.c

So prepare to make one more clean of early_res.c.

-v2: don't need to reserve first page in early_res
     because we already mark that in e820 as reserved already.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
LKML-Reference: <1265793639-15071-20-git-send-email-yinghai@kernel.org>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>