cnss: Add wrapper functions for work queue functionalities

Add wrapper functions for cancel_work_sync and
cancel_delayed_work_sync kernel APIs

Change-Id: Ifad868794de2e7c8abf52cf736a6b06394efe87a
CRs-Fixed: 583276
Acked-by: Mahesh Kumar Edhar <c_medhar@qti.qualcomm.com>
Signed-off-by: Sameer Thalappil <sameert@codeaurora.org>