Broadcom driver can cause kernel panic when used with virtual interface. Blacklist it.

Fixes #203

create_ap

@@ -279,6 +279,13 @@ get_adapter_kernel_module() {
 can_be_sta_and_ap() {
     # iwconfig does not provide this information, assume false
     [[ $USE_IWCONFIG -eq 1 ]] && return 1
+    if [[ "$(get_adapter_kernel_module "$1")" == "brcmfmac" ]]; then
+        echo "WARN: brmfmac driver doesn't work properly with virtual interfaces and" >&2
+        echo "      it can cause kernel panic. For this reason we disallow virtual" >&2
+        echo "      interfaces for your adapter." >&2
+        echo "      For more info: https://github.com/oblique/create_ap/issues/203" >&2
+        return 1
+    fi
     get_adapter_info "$1" | grep -E '{.* managed.* AP.*}' > /dev/null 2>&1 && return 0
     get_adapter_info "$1" | grep -E '{.* AP.* managed.*}' > /dev/null 2>&1 && return 0
     return 1