Input: ALPS - put secondary device in proper place in sysfs

Secondary input device did not have parent set up causing it
to appear in the root of sysfs device hierarchy.
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>

drivers/input/mouse/alps.c

@@ -483,6 +483,7 @@ int alps_init(struct psmouse *psmouse)
 	dev2->id.vendor  = 0x0002;
 	dev2->id.product = PSMOUSE_ALPS;
 	dev2->id.version = 0x0000;
+	dev2->dev.parent = &psmouse->ps2dev.serio->dev;
 
 	dev2->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_REL);
 	dev2->relbit[BIT_WORD(REL_X)] |= BIT_MASK(REL_X) | BIT_MASK(REL_Y);