msm: ipa: improve error handling in ipa_qmi_service_init

In case of failures in creating workqueues in
ipa_qmi_service_init_worker add error messages and freeing of the
already created/registered handles.
Add checks in ipa_qmi_service_exit that handles and workqueues are
not NULL before destroying them.

CRs-Fixed: 728668
Change-Id: Ib53f309dae14472d34b2181e87aa0f7638d5d540
Signed-off-by: Sivan Reinstein <sivanr@codeaurora.org>