MMC: omap_hsmmc.c: Add missing prototype header

Add missing header file to fix compilation warning

omap_hsmmc.c: In function 'omap_mmc_init':
omap_hsmmc.c:474: warning: implicit declaration of function 'get_cpu_family'
omap_hsmmc.c:474: warning: implicit declaration of function 'get_cpu_rev'

introduced by commit "MMC: omap_hsmmc.c: disable
multiblock rw on old rev omap34xx silicon"
(4ca9244d74)

Signed-off-by: Dirk Behme <dirk.behme@googlemail.com>
CC: Andy Fleming <afleming@freescale.com>
CC: John Rigby <john.rigby@linaro.org>

drivers/mmc/omap_hsmmc.c

@@ -30,6 +30,7 @@
 #include <twl4030.h>
 #include <asm/io.h>
 #include <asm/arch/mmc_host_def.h>
+#include <asm/arch/sys_proto.h>
 
 /* If we fail after 1 second wait, something is really bad */
 #define MAX_RETRY_MS	1000