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

drivers/gpu/drm/i915/display/intel_dp_hdcp.c

@@ -532,7 +532,7 @@ int intel_dp_hdcp2_read_msg(struct intel_digital_port *dig_port,
 	u8 *byte = buf;
 	ssize_t ret, bytes_to_recv, len;
 	const struct hdcp2_dp_msg_data *hdcp2_msg_data;
-	ktime_t msg_end;
+	ktime_t msg_end = ktime_set(0, 0);
 	bool msg_expired;
 
 	hdcp2_msg_data = get_hdcp2_dp_msg_data(msg_id);