With the new i.mx clock framework the i2c clock is registered as:

clk_register_clkdev(clk[i2c1_ipg_gate], NULL, "imx-i2c.0")

So we do not need to pass "i2c_clk" string and can use NULL instead.
Signed-off-by: NFabio Estevam <fabio.estevam@freescale.com>
Acked-by: NSascha Hauer <s.hauer@pengutronix.de>

[wsa: rebased on top of the devm-conversion]
Signed-off-by: NWolfram Sang <w.sang@pengutronix.de>