am33xx: refactor emif4/ddr to support multiple EMIF instances

The AM33xx emif4/ddr support closely matches what is need to support
TI814x except that TI814x has two EMIF instances. Refactor all the
emif4 helper calls and the config_ddr() init function to use an
additional instance number argument.

Signed-off-by: Matt Porter <mporter@ti.com>
Reviewed-by: Tom Rini <trini@ti.com>
6 files changed