cnss2: Ignore RDDM failure if MHI is not powered on

When triggering RDDM fails, if MHI is not powered on or driver
unload/idle shutdown is in progress, there is no need to do
recovery. Hence ignore the failure in such scenario.

Change-Id: I4b14bf31cd71bf80b61a02745a4a506e93a4a16c
Signed-off-by: Yue Ma <yuem@codeaurora.org>