drm/i915/hdcp: Fix uninitialized symbol 'msg_end'

Fix static analysis tool uninitialized symbol error.

v2:
- use ktime_set(0, 0) instead to initialize to zero. [Ankit]

Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Anshuman Gupta <anshuman.gupta@intel.com>
Reviewed-by: Ankit Nautiyal <ankit.k.nautiyal@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210408082642.27066-1-anshuman.gupta@intel.com