headers: Sync up some comment spelling and whitespace fixes from drm-next.

This pulls in pieces of drm-next d65d31388a23
("Merge tag 'drm-misc-next-fixes-2017-11-07' of
git://anongit.freedesktop.org/drm/drm-misc into drm-next")

Signed-off-by: Eric Anholt <eric@anholt.net>
Reviewed-by: Emil Velikov <emil.l.velikov@gmail.com>
diff --git a/include/drm/mga_drm.h b/include/drm/mga_drm.h
index f54e7a2..7035a66 100644
--- a/include/drm/mga_drm.h
+++ b/include/drm/mga_drm.h
@@ -111,7 +111,7 @@
  */
 #define MGA_NR_SAREA_CLIPRECTS	8
 
-/* 2 heaps (1 for card, 1 for agp), each divided into upto 128
+/* 2 heaps (1 for card, 1 for agp), each divided into up to 128
  * regions, subject to a minimum region size of (1<<16) == 64k.
  *
  * Clients may subdivide regions internally, but when sharing between