usb: storage: Replace mdelay with msleep in init_freecom

init_freecom() is never called in atomic context.

init_freecom() is set as ".initFunction" through UNUSUAL_DEV().
And ->initFunction() is only called by usb_stor_acquire_resources(),
which is only called by usb_stor_probe2().
usb_stor_probe2() is called by *_probe() functions (like alauda_probe())
for each USB driver.
*_probe() functions are set ".probe" in struct usb_driver.
These functions are not called in atomic context.

Despite never getting called from atomic context, init_freecom()
calls mdelay() to busily wait.
This is not necessary and can be replaced with msleep() to
avoid busy waiting.

This is found by a static analysis tool named DCNS written by myself.
And I also manually check it.

Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/storage/freecom.c

@@ -464,7 +464,7 @@ static int init_freecom(struct us_data *us)
 	usb_stor_dbg(us, "result from activate reset is %d\n", result);
 
 	/* wait 250ms */
-	mdelay(250);
+	msleep(250);
 
 	/* clear reset */
 	result = usb_stor_control_msg(us, us->send_ctrl_pipe,
@@ -472,7 +472,7 @@ static int init_freecom(struct us_data *us)
 	usb_stor_dbg(us, "result from clear reset is %d\n", result);
 
 	/* wait 3 seconds */
-	mdelay(3 * 1000);
+	msleep(3 * 1000);
 
 	return USB_STOR_TRANSPORT_GOOD;
 }