defconfigs: Add config for AM57xx High Security EVM with USB/UART Boot support

Add a new defconfig file for the AM57xx High Security EVM. This config
is specific for the case of USB/UART booting.

Signed-off-by: Andrew F. Davis <afd@ti.com>
Reviewed-by: Tom Rini <trini@konsulko.com>
2 files changed