v64_intrinsics.h: fix v64_align signature
v64_intrinsics.h: fix v64_align signature

add correct type for 'c' parameter

BUG=aomedia:500

Change-Id: I4ea2334405d8d7ea436bc373dd1c812666f98067

GrokImageCompression/aom,GrokImageCompression/aom,GrokImageCompression/aom,GrokImageCompression/aom,GrokImageCompression/aom,GrokImageCompression/aom