hw/xwin: Fix rrScreenSetSize function pointer mismatch

winrandr.c: In function ‘winRandRInit’:
winrandr.c:218:31: warning: assignment from incompatible pointer type

Fix winRandRScreenSetSize() function signature to match RRScreenSetSizeProcPtr type,
to align with commit fd9331f6 'Revert "Separate out screen size and screen pixmap
sizes in RRScreenSizeSet"'

This is fall-out from the late revert of RANDR 1.4 in the 1.10 release cycle, it will
probably need to be reverted if/when that goes back in again.

Signed-off-by: Ryan Pavlik <rpavlik@iastate.edu>
Reviewed-by: Colin Harrison <colin.harrison@virgin.net>
Reviewed-by: Jon TURNEY <jon.turney@dronecode.org.uk>

hw/xwin/winrandr.c

@@ -122,8 +122,6 @@ Bool
 winRandRScreenSetSize (ScreenPtr  pScreen,
 		       CARD16	    width,
 		       CARD16	    height,
-		       CARD16       pixWidth,
-		       CARD16       pixHeight,
 		       CARD32	    mmWidth,
 		       CARD32	    mmHeight)
 {