x86: cache_info: Update calculation of AMD L3 cache indices

L3 subcaches 0 and 1 of AMD Family 15h CPUs can have a size of 2MB.
Update the calculation routine for the number of L3 indices to
reflect that.

Signed-off-by: Frank Arnold <frank.arnold@amd.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Rosenfeld Hans <Hans.Rosenfeld@amd.com>
Cc: Herrmann3 Andreas <Andreas.Herrmann3@amd.com>
Cc: Mike Travis <travis@sgi.com>
Cc: Frank Arnold <Frank.Arnold@amd.com>
Link: http://lkml.kernel.org/r/20110726170449.GB32536@aftab


Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>