Input: altera_ps2 - write to correct register when disabling interrupts

commit d0269b84 upstream.

In altera_ps2_close, the data register (offset 0) is written instead of
the control register (offset 4), leading to the RX interrupt not being
disabled. Fix this by calling writel() with the offset for the proper
register.

Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>