am33xx: Rework pinmux functions

- Move definition of the EEPROM contents to <asm/arch/sys_proto.h>
  - Make some defines a little less generic now.
- Pinmux must be done by done by SPL now.
- Create 3 pinmux functions, uart0, i2c0 and board.
- Add pinmux specific to Starter Kit EVM for MMC now.

Signed-off-by: Tom Rini <trini@ti.com>
5 files changed