matroxfb: avoid -Warray-bounds warning

The open-coded list_for_each_entry() causes a harmless warning:

drivers/video/fbdev/matrox/matroxfb_base.c: In function 'matroxfb_register_driver':
include/linux/kernel.h:856:3: warning: array subscript -98 is outside array bounds of 'struct list_head[1]' [-Warray-bounds]

Use the normal list_for_each_entry instead.

Fixes: 1da177e4 ("Linux-2.6.12-rc2")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20201026194010.3817166-1-arnd@kernel.org

drivers/video/fbdev/matrox/matroxfb_base.c

@@ -1970,9 +1970,7 @@ int matroxfb_register_driver(struct matroxfb_driver* drv) {
 	struct matrox_fb_info* minfo;
 
 	list_add(&drv->node, &matroxfb_driver_list);
-	for (minfo = matroxfb_l(matroxfb_list.next);
-	     minfo != matroxfb_l(&matroxfb_list);
-	     minfo = matroxfb_l(minfo->next_fb.next)) {
+	list_for_each_entry(minfo, &matroxfb_list, next_fb) {
 		void* p;
 
 		if (minfo->drivers_count == MATROXFB_MAX_FB_DRIVERS)
@@ -1990,9 +1988,7 @@ void matroxfb_unregister_driver(struct matroxfb_driver* drv) {
 	struct matrox_fb_info* minfo;
 
 	list_del(&drv->node);
-	for (minfo = matroxfb_l(matroxfb_list.next);
-	     minfo != matroxfb_l(&matroxfb_list);
-	     minfo = matroxfb_l(minfo->next_fb.next)) {
+	list_for_each_entry(minfo, &matroxfb_list, next_fb) {
 		int i;
 
 		for (i = 0; i < minfo->drivers_count; ) {