ADB sideload command not work

In kernel(3.10) USB ADB gadget driver is removed.
Using Functionfs for USB adb gadget.

Android recovery uses a stripped down version
of adb command for sideload only. It's missing
the ffs function support, so add the ffs
support to allow sideload command to work

b/12608946

Change-Id: I4ad024723dfc5bdb544548391f99637c390b171e
Signed-off-by: Pierre Couillaud <pierre@broadcom.com>
diff --git a/minadbd/adb.c b/minadbd/adb.c
index 948f4b7..7291b4b 100644
--- a/minadbd/adb.c
+++ b/minadbd/adb.c
@@ -387,7 +387,7 @@
     init_transport_registration();
 
     // The minimal version of adbd only uses USB.
-    if (access("/dev/android_adb", F_OK) == 0) {
+    if (access(USB_ADB_PATH, F_OK) == 0 || access(USB_FFS_ADB_EP0, F_OK) == 0) {
         // listen on USB
         usb_init();
     }