ARM: davinci: cpufreq: fix compiler warning

This fixes:
	arch/arm/mach-davinci/cpufreq.c: In function davinci_target:
	arch/arm/mach-davinci/cpufreq.c:98: warning: passing argument 2 of dev_printk from incompatible pointer type

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Sekhar Nori <nsekhar@ti.com>