drm/qxl: move extern variable declaration header file

Flagged by sparse.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Acked-by: Daniel Vetter <daniel@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20170620113916.6967-4-kraxel@redhat.com

drivers/gpu/drm/qxl/qxl_drv.c

@@ -37,7 +37,6 @@
 #include "qxl_drv.h"
 #include "qxl_object.h"
 
-extern int qxl_max_ioctls;
 static const struct pci_device_id pciidlist[] = {
 	{ 0x1b36, 0x100, PCI_ANY_ID, PCI_ANY_ID, PCI_CLASS_DISPLAY_VGA << 8,
 	  0xffff00, 0 },