x86/platform/UV: Fix GAM MMR changes in UV4A

Intel processor changes necessitated UV4 HUB Global Address Memory
(GAM) fixes to accommodate support for those processors.  This patch
deals with the updated address range change from 46 to 52 bits in UV4A.

Signed-off-by: Mike Travis <mike.travis@hpe.com>
Acked-by: Andrew Banman <abanman@hpe.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Dimitri Sivanich <sivanich@hpe.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Russ Anderson <rja@hpe.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1515440405-20880-5-git-send-email-mike.travis@hpe.com


Signed-off-by: Ingo Molnar <mingo@kernel.org>