USB: musb: minor locking fix

Minor locking fix for musb_hdrc on OMAP3 and OMAP2430:
don't read DEVCTL without holding the spinlock, since
an IRQ could come in and corrupt things.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Felipe Balbi <felipe.balbi@nokia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/usb/musb/omap2430.c

@@ -58,10 +58,10 @@ static void musb_do_idle(unsigned long _musb)
 #endif
 	u8	devctl;
 
-	devctl = musb_readb(musb->mregs, MUSB_DEVCTL);
-
 	spin_lock_irqsave(&musb->lock, flags);
 
+	devctl = musb_readb(musb->mregs, MUSB_DEVCTL);
+
 	switch (musb->xceiv.state) {
 	case OTG_STATE_A_WAIT_BCON:
 		devctl &= ~MUSB_DEVCTL_SESSION;