ARM: SoC cleanups for v4.2

A relatively small setup of cleanups this time around, and similar to last time
the bulk of it is removal of legacy board support:

- OMAP: removal of legacy (non-DT) booting for several platforms
- i.MX: remove some legacy board files

Conflicts: None

# gpg: Signature made Wed Jun 24 21:32:09 2015 PDT using RSA key ID D3FBC665
# gpg: Good signature from "Kevin Hilman <khilman@deeprootsystems.com>"
# gpg:                 aka "Kevin Hilman <khilman@linaro.org>"
# gpg:                 aka "Kevin Hilman <khilman@kernel.org>"