platform: msm: check for codec ops

Check if the codec driver has registered with ext-display
module. If not, return early with error to avoid crash
where it may try to access codec driver's data.

CRs-Fixed: 2020938
Change-Id: I1bd7c9a8551bff32c4e5c2141e118dc097d906c4
Signed-off-by: Ajay Singh Parmar <aparmar@codeaurora.org>