target-i386: Add Core Duo Definition

This patch adds a CPU definition for the Core Duo CPU. I tried to
resemble the original as closely as possible and document what features
are missing still. This patch enables the use of a recent CPU definition
on 32 bit platforms.

It also fixes two issues that went along the line:

- invalid xlevel in core2duo spec
  While looking though the CPUIDs again, I found that xlevel is actually 8.

- non-PSE36 support
  The CoreDuo CPUID does not expose the PSE36 capability, but CPUID
0x80000008 is tied to 36 bits. This broke Windows XP installation for
me, so I just set it to 32 bits width when PSE36 is not available. The
original CPU also exposes 32 bit width in CPUID 0x80000008.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>

git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@5488 c046a42c-6fe2-441c-8c8c-71466251a162
