qcacmn: Correct the error handling in event registration

wmi_oem_response_event_id is only defined for TLV based
architectures. Current code returns an error if registration to a
particular event fails. But registration failure is not wrong
for legacy architectures, as event is not defined.
So do not check return value for error

Change-Id: Ia54431cee2958b59166394360a3fc961abad85ce
CRs-Fixed: 2492494
1 file changed