arm: omap: musb: we can use clk framework

... in order to handle musb's clock. Let's start
removing the old musb-only set_clock function.

Cc: linux-usb@vger.kernel.org
Signed-off-by: Felipe Balbi <felipe.balbi@nokia.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>

arch/arm/mach-omap2/usb-musb.c

@@ -47,27 +47,6 @@ static struct resource musb_resources[] = {
 	},
 };
 
-static int clk_on;
-
-static int musb_set_clock(struct clk *clk, int state)
-{
-	if (state) {
-		if (clk_on > 0)
-			return -ENODEV;
-
-		clk_enable(clk);
-		clk_on = 1;
-	} else {
-		if (clk_on == 0)
-			return -ENODEV;
-
-		clk_disable(clk);
-		clk_on = 0;
-	}
-
-	return 0;
-}
-
 static struct musb_hdrc_config musb_config = {
 	.multipoint	= 1,
 	.dyn_fifo	= 1,
@@ -88,7 +67,6 @@ static struct musb_hdrc_platform_data musb_plat = {
 	.mode		= MUSB_PERIPHERAL,
 #endif
 	/* .clock is set dynamically */
-	.set_clock	= musb_set_clock,
 	.config		= &musb_config,
 
 	/* REVISIT charge pump on TWL4030 can supply up to