ARM: clk-imx27: Add missing clock for mx2-camera

During the clock conversion for mx27 the "per4_gate" clock was missed to get
registered as a dependency of mx2-camera driver.

In the old mx27 clock driver we used to have:

DEFINE_CLOCK1(csi_clk, 0, NULL, 0, parent, &csi_clk1, &per4_clk);

,so does the same in the new clock driver
Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Acked-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

arch/arm/mach-imx/clk-imx27.c

@@ -235,6 +235,7 @@ int __init mx27_clocks_init(unsigned long fref)
 	clk_register_clkdev(clk[lcdc_ipg_gate], "ipg", "imx21-fb.0");
 	clk_register_clkdev(clk[lcdc_ahb_gate], "ahb", "imx21-fb.0");
 	clk_register_clkdev(clk[csi_ahb_gate], "ahb", "imx27-camera.0");
+	clk_register_clkdev(clk[per4_gate], "per", "imx27-camera.0");
 	clk_register_clkdev(clk[usb_div], "per", "fsl-usb2-udc");
 	clk_register_clkdev(clk[usb_ipg_gate], "ipg", "fsl-usb2-udc");
 	clk_register_clkdev(clk[usb_ahb_gate], "ahb", "fsl-usb2-udc");