wil6210: prevent XTAL off in device bootloader

Device bootloader enters deep sleep and turns off
its clock after 1 second of inactivity.
Waking up from this stage takes several milliseconds
and can cause PCIe timeout.
To prevent that, we need to add HALP vote in the reset
flow which will prevent the BL from turning off its
XTAL.

Change-Id: Id9273e546d3565935a7b1150c27993f02c5734e3
Signed-off-by: Maya Erez <merez@codeaurora.org>