Use proper build config for parsing proxy_arp

In the definition of struct hostapd_bss_config, proxy_arp isn't affected
by the macro CONFIG_HS20. In addition, proxy_arp is not described in the
section of Hotspot 2.0 in the file hostapd.conf. The item proxy_arp
should be decided its action area by the macro CONFIG_PROXYARP which is
used to select whether the needed function gets included in the build.

Signed-off-by: Matt Woods <matt.woods@aliyun.com>

hostapd/config_file.c

@@ -3206,13 +3206,15 @@ static int hostapd_config_fill(struct hostapd_config *conf,
 		os_free(bss->dump_msk_file);
 		bss->dump_msk_file = os_strdup(pos);
 #endif /* CONFIG_RADIUS_TEST */
+#ifdef CONFIG_PROXYARP
+	} else if (os_strcmp(buf, "proxy_arp") == 0) {
+		bss->proxy_arp = atoi(pos);
+#endif /* CONFIG_PROXYARP */
 #ifdef CONFIG_HS20
 	} else if (os_strcmp(buf, "hs20") == 0) {
 		bss->hs20 = atoi(pos);
 	} else if (os_strcmp(buf, "disable_dgaf") == 0) {
 		bss->disable_dgaf = atoi(pos);
-	} else if (os_strcmp(buf, "proxy_arp") == 0) {
-		bss->proxy_arp = atoi(pos);
 	} else if (os_strcmp(buf, "na_mcast_to_ucast") == 0) {
 		bss->na_mcast_to_ucast = atoi(pos);
 	} else if (os_strcmp(buf, "osen") == 0) {