wl12xx: removed chipset interrupt source configuration from fw wakeup

The chipset source interrupt source configuration during fw wakeup was
blocking interrupts on the wl1271. The configuration is effectively
unused here as it is used to trigger an interrupt for the chipset
wake-up event, which is not handled, or waited for, in the fw wakeup
anyway on either wl1251 or wl1271.

Signed-off-by: Juuso Oikarinen <juuso.oikarinen@nokia.com>
Signed-off-by: Luciano Coelho <luciano.coelho@nokia.com>
Signed-off-by: Kalle Valo <kalle.valo@nokia.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>