ath10k: wait for FW ready during initialization

Since the qmi service in snoc driver gets registered late,
it misses the first time FW ready is sent. This causes the
wait on FW ready to fail and eventually the driver loading fails.

Proceed with the driver initialization only once the FW ready
indication arrives. Handle error in case the wait for these
events timeout.

Change-Id: Ib20ddb3a2f8b5b48936cc97b38f637f31e4e0100
Signed-off-by: Rakesh Pillai <pillair@codeaurora.org>