qcacld-3.0: Remove including subsystem_restart.h from wlan_hdd_main.c

In wlan_hdd_main.c file, there is no reference to any interface from
subsystem_restart.h, so remove it to avoid compilation errors since
subsystem_restart.h is no longer supported and the file is not present
latest msm-kalama kernel.

Change-Id: Id5858bf436a44f612bab15f341bf0dc8dafc90f2
CRs-fixed: 3060053

core/hdd/src/wlan_hdd_main.c

@@ -88,9 +88,6 @@
 #include "qdf_periodic_work.h"
 #endif
 
-#ifdef MSM_PLATFORM
-#include <soc/qcom/subsystem_restart.h>
-#endif
 #include <wlan_hdd_hostapd.h>
 #include <wlan_hdd_softap_tx_rx.h>
 #include <wlan_hdd_green_ap.h>