cnss2: Save PCIe config space in no_irq phrase if link is up

If disabling power collapse is true, PCIe link will not be suspended
by MSM PCIe driver during system suspend. Save the config space in
no_irq phrase otherwise PCIe framework will try to save it and then set
D3 state while link is still up. During system suspend, PCIe framework
will restore it so there is no need to restore again in the driver.

Change-Id: I4c725df680bac041f2b5ba84f08c68aa7acec7ce
Signed-off-by: Yue Ma <yuem@codeaurora.org>