oprofile/x86: add Xeon 7500 series support

Add Xeon 7500 series support to oprofile.

Straight forward: it's the same as Core i7, so just detect
the model number. No user space changes needed.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Robert Richter <robert.richter@amd.com>