tests: Prepare ap_open_out_of_memory for modified rfkill init path

The rfkill initialization will be moved out from
wpa_driver_nl80211_drv_init() which would break one step in this OOM
test case due to the memory allocation not existing anymore. Fix this by
skipping that OOM step to avoid causing false failures with the
following commits.

Signed-off-by: Jouni Malinen <j@w1.fi>

tests/hwsim/test_ap_open.py

@@ -213,7 +213,7 @@ def test_ap_open_out_of_memory(dev, apdev):
 
     hapd_out_of_mem(hapd, apdev[1], 1, "hostapd_driver_init")
 
-    for i in range(1, 4):
+    for i in range(1, 3):
         hapd_out_of_mem(hapd, apdev[1], i, "=wpa_driver_nl80211_drv_init")
 
     # eloop_register_read_sock() call from i802_init()