video: fbdev: xen: remove setting of 'transp' parameter

cppcheck reports
[drivers/video/fbdev/xen-fbfront.c:226]: (style) Assignment of function parameter has no effect outside the function.

The value parameter 'transp' is not used, so setting it can be removed.
Signed-off-by: Tom Rix <trix@redhat.com>
Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Reviewed-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Helge Deller <deller@gmx.de>

drivers/video/fbdev/xen-fbfront.c

@@ -224,7 +224,6 @@ static int xenfb_setcolreg(unsigned regno, unsigned red, unsigned green,
 	red = CNVT_TOHW(red, info->var.red.length);
 	green = CNVT_TOHW(green, info->var.green.length);
 	blue = CNVT_TOHW(blue, info->var.blue.length);
-	transp = CNVT_TOHW(transp, info->var.transp.length);
 #undef CNVT_TOHW
 
 	v = (red << info->var.red.offset) |