msm: pcie: Enable WAKE IRQ all the time

When WLAN driver has suspended but PCIe bus driver has not
suspended yet, there is a small window that WiFi HW asserts WAKE
gpio but the wake IRQ is not enabled yet. Thus, PCIe bus driver
will enable WAKE IRQ all the time and abort any ongoing suspend
process after receives WAKE IRQ.

Change-Id: I3fc199c7b165ed00f3db9eee5eabc08faaf96e34
Signed-off-by: Yan He <yanhe@codeaurora.org>