imx-common: consolidate macros and prototypes into sys_proto.h

imx-common: consolidate macros and prototypes into sys_proto.h

Move most macro definitions and prototypes into
"arch/arm/include/asm/imx-common/sys_proto.h" to avoid duplicated
function prototypes and marco definitions for different i.MX SoCs.

This patch do not remove the sys_proto.h for different i.MX SoCs,
because we need to modify lots of driver code and others. This patch
remove duplicated macros and prototypes and incude "sys_proto.h"
of imx-common for each sys_proto.h of different i.MX platforms.
Then later we should avoid add stuff in sys_proto.h of each platform,
and modify driver to include common sys_proto.h.

Signed-off-by: Peng Fan <Peng.Fan@freescale.com>
Cc: Stefano Babic <sbabic@denx.de>
Reviewed-by: Stefano Babic <sbabic@denx.de>