drm/radeon: add PX quirk for asus K53TK

Seems to have problems turning the dGPU on/off.

bug:
https://bugzilla.kernel.org/show_bug.cgi?id=51381

Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/radeon/radeon_device.c

@@ -123,6 +123,10 @@ static struct radeon_px_quirk radeon_px_quirk_list[] = {
 	 * https://bugzilla.kernel.org/show_bug.cgi?id=51381
 	 */
 	{ PCI_VENDOR_ID_ATI, 0x6741, 0x1043, 0x108c, RADEON_PX_QUIRK_DISABLE_PX },
+	/* Asus K53TK laptop with AMD A6-3420M APU and Radeon 7670m GPU
+	 * https://bugzilla.kernel.org/show_bug.cgi?id=51381
+	 */
+	{ PCI_VENDOR_ID_ATI, 0x6840, 0x1043, 0x2122, RADEON_PX_QUIRK_DISABLE_PX },
 	/* macbook pro 8.2 */
 	{ PCI_VENDOR_ID_ATI, 0x6741, PCI_VENDOR_ID_APPLE, 0x00e2, RADEON_PX_QUIRK_LONG_WAKEUP },
 	{ 0, 0, 0, 0, 0 },