ARM: clk-imx35: Fix build warnings with W=1

Fix the following warnings when building with W=1 option:

arch/arm/mach-imx/clk-imx35.c: In function 'mx35_clocks_init':
arch/arm/mach-imx/clk-imx35.c:70:12: warning: old-style function definition [-Wold-style-definition]
arch/arm/mach-imx/clk-imx35.c:201:16: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>