mwifiex: Enable WoWLAN for both sdio and pcie

Commit ce4f6f0c ("mwifiex: add platform specific wakeup interrupt
support") added WoWLAN feature only for sdio. This patch moves that
code to the common module so that all the interface drivers can use
it for free. It enables pcie and sdio for its use currently.

Signed-off-by: Rajat Jain <rajatja@google.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>