msm: ipa: clear uc response before sending clk commands

This change is needed to ensure uc response is not wiped out
prior to polling for the same.

Change-Id: I69acb78b9c9dd33e511539670b6e3b7d28c1c97a
Signed-off-by: Ravi Gummadidala <rgummadi@codeaurora.org>