Include <mach/common.h> header to fix the following sparse warning:

arch/arm/mach-mxs/ocotp.c:33:11: warning: symbol 'mxs_get_ocotp' was not declared. Should it be static?
Signed-off-by: NFabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: NShawn Guo <shawn.guo@linaro.org>

I get this build error as of today:

arch/arm/mach-mxs/ocotp.c: In function 'mxs_get_ocotp':
arch/arm/mach-mxs/ocotp.c:54: error: implicit declaration of function 'cpu_relax'
make[2]: *** [arch/arm/mach-mxs/ocotp.o] Error 1

Looks like it has been indirectly included before which broke now.
Include it directly.
Signed-off-by: NWolfram Sang <w.sang@pengutronix.de>
Cc: Shawn Guo <shawn.guo@freescale.com>
Signed-off-by: NSascha Hauer <s.hauer@pengutronix.de>

Signed-off-by: NShawn Guo <shawn.guo@freescale.com>
Signed-off-by: NSascha Hauer <s.hauer@pengutronix.de>