PM / hibernate: Declare variables as static

Fixing sparse warnings: 'symbol not declared. Should it be static?'
Signed-off-by: NPushkar Jambhlekar <pushkar.iit@gmail.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

kernel/power/snapshot.c

@@ -1422,7 +1422,7 @@ static unsigned int nr_meta_pages;
  * Numbers of normal and highmem page frames allocated for hibernation image
  * before suspending devices.
  */
-unsigned int alloc_normal, alloc_highmem;
+static unsigned int alloc_normal, alloc_highmem;
 /*
  * Memory bitmap used for marking saveable pages (during hibernation) or
  * hibernation image pages (during restore)