platform: msm: usb_bam: Fix potential use-after-free in connect_pipe

In the connect_pipe() failure path, the allocated pipe is freed but
the pointer variable is not reset creating a dangling pointer and
potential UaF if it is later accessed.  Fix it by assigning it to NULL.

Change-Id: Iae9fb05ce819fc94839180762393fa18aaecdd60
Signed-off-by: Jack Pham <[email protected]>

drivers/platform/msm/usb_bam.c

@@ -866,6 +866,7 @@ static int connect_pipe(enum usb_ctrl cur_bam, u8 idx, u32 *usb_pipe_idx,
 	sps_disconnect(*pipe);
 free_sps_endpoint:
 	sps_free_endpoint(*pipe);
+	*pipe = NULL;
 	return ret;
 }