comctl32: Constify some variables (10 of 12)

[Andrew Talbot]

Changelog:
    comctl32: Constify some variables.

diff -urN a/dlls/comctl32/smoothscroll.c b/dlls/comctl32/smoothscroll.c
--- a/dlls/comctl32/smoothscroll.c	2006-10-20 18:07:57.000000000 +0100
+++ b/dlls/comctl32/smoothscroll.c	2007-03-31 16:04:52.000000000 +0100
@@ -68,7 +68,7 @@
  *     Currently only scrolls ONCE. The comctl32 implementation uses GetTickCount
  *     and what else to do smooth scrolling.
  */
-BOOL WINAPI SmoothScrollWindow( SMOOTHSCROLLSTRUCT *smooth ) {
+BOOL WINAPI SmoothScrollWindow( const SMOOTHSCROLLSTRUCT *smooth ) {
    LPRECT	lpupdaterect = smooth->lpupdaterect;
    HRGN		hrgnupdate = smooth->hrgnupdate;
    RECT		tmprect;