Fix null pointer dereference in HACK_acl_check_sm4

fix to return when p_acl is null to avoid null pointer dereference
problem.

Sponsor: cmanton@
Bug: 198338740
Tag: #refactor
Test: gd/cert/run

Change-Id: I45408a2b024dc424442bf3c2f92293b8942b54bb
Signed-off-by: Dowon Park <dowon.park@samsung.com>