Documentation/kernel-parameters.txt: replace kernelcore with Movable

Han Pingtian found a typo in Documentation/kernel-parameters.txt about
"kernelcore=", that "kernelcore" should be replaced with "Movable" here.

Signed-off-by: Weiping Pan <wpan@redhat.com>
Acked-by: Mel Gorman <mgorman@suse.de>
Cc: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Documentation/kernel-parameters.txt

@@ -1357,7 +1357,7 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
 			pages. In the event, a node is too small to have both
 			kernelcore and Movable pages, kernelcore pages will
 			take priority and other nodes will have a larger number
-			of kernelcore pages.  The Movable zone is used for the
+			of Movable pages.  The Movable zone is used for the
 			allocation of pages that may be reclaimed or moved
 			by the page migration subsystem.  This means that
 			HugeTLB pages may not be allocated from this zone.