am33xx: Finish migration of CONFIG_AM33XX/AM43XX

Almost all users of CONFIG_AM33XX/AM43XX have been migrated.  Finish
moving the last few over to Kconfig, and put all of the boards under the
appropriate Kconfig chocie now.  This board choice is non-optional, so
remove that keyword on am33xx.

Signed-off-by: Tom Rini <trini@konsulko.com>
16 files changed