ARM i.MX: remove now unnecessary argument from mxc_timer_init

As the timer code now does a clk_get to get its clock we don't
need the struct clk argument anymore.
This also changes the alternative EPIT timer to do a clk_get.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
diff --git a/arch/arm/mach-imx/clk-imx25.c b/arch/arm/mach-imx/clk-imx25.c
index d9833bb..fdd8cc8 100644
--- a/arch/arm/mach-imx/clk-imx25.c
+++ b/arch/arm/mach-imx/clk-imx25.c
@@ -243,6 +243,6 @@
 	clk_register_clkdev(clk[sdma_ahb], "ahb", "imx35-sdma");
 	clk_register_clkdev(clk[iim_ipg], "iim", NULL);
 
-	mxc_timer_init(NULL, MX25_IO_ADDRESS(MX25_GPT1_BASE_ADDR), 54);
+	mxc_timer_init(MX25_IO_ADDRESS(MX25_GPT1_BASE_ADDR), 54);
 	return 0;
 }