msm: ipa3: add check on sending new uc-op codes

Add the check on checking if uc_event_ring_valid
is valid or not before sending the new uc OP codes
commands to ipa-uc.

Change-Id: Ic535250fd58444a577415ddeff724541acd5f666
Signed-off-by: Skylar Chang <chiaweic@codeaurora.org>