hwrng: imx-rngc - mark the probe function as __init

Mark the imx_rngc_probe function as __init.

There's no need to support hotplugging in the imx-rngc driver. We use
module_platform_driver_probe, the probe function will only be called at
startup.
Signed-off-by: Martin Kaiser <martin@kaiser.cx>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

drivers/char/hw_random/imx-rngc.c

@@ -224,7 +224,7 @@ static void imx_rngc_cleanup(struct hwrng *rng)
 	imx_rngc_irq_mask_clear(rngc);
 }
 
-static int imx_rngc_probe(struct platform_device *pdev)
+static int __init imx_rngc_probe(struct platform_device *pdev)
 {
 	struct imx_rngc *rngc;
 	int ret;