USB: Handle allocated buffer freeing after error and unused variables

Free the allocated buffer after an error and remove
unused variables.

CRs-Fixed: 313681
Change-Id: I76ebf946eacac47682a3c510cd7beed3fc3c6437
Signed-off-by: Rajkumar Raghupathy <raghup@codeaurora.org>
diff --git a/drivers/usb/gadget/android.c b/drivers/usb/gadget/android.c
index 8d58833..fdd0ba8 100644
--- a/drivers/usb/gadget/android.c
+++ b/drivers/usb/gadget/android.c
@@ -817,6 +817,7 @@
 				&common->luns[0].dev.kobj,
 				"lun");
 	if (err) {
+		fsg_common_release(&common->ref);
 		kfree(config);
 		return err;
 	}