wifi: cfg80211: tests: Fix potential NULL dereference in test_cfg80211_parse_colocated_ap()

In the Linux kernel, the following vulnerability has been resolved: wifi: cfg80211: tests: Fix potential NULL dereference in test_cfg80211_parse_colocated_ap() kunit_kzalloc() may return NULL, dereferencing it without NULL check may lead to NULL dereference. Add a NULL check for ies.