When OOB is disabled, FW will be power gated when system is in S3/S4/S5
which is the same behavior with legacy ISH FW.
When OOB is enabled, FW will always power on which is totally different
comparing to legacy ISH FW.

So NO_D3 flag is not enough to check FW's status after resume.
Here we can use IPC FW status register to check host link status.
If it is false, it means FW get reset after power gated, need go through
the whole initialization flow; If it is true, it means FW is alive, just
set host ready bit to let fw know host is up.
Co-developed-by: Wei Jiang <wei.w.jiang@intel.com>
Signed-off-by: Wei Jiang <wei.w.jiang@intel.com>
Signed-off-by: Even Xu <even.xu@intel.com>
Signed-off-by: Zhang Lixu <lixu.zhang@intel.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>