boards: Remove empty BOARD_SPECIFIC_OPTIONS

While there are currently uses for a stanza of "config BOARD_SPECIFIC_OPTIONS"
followed by "def_bool y" and a series of select/imply statements, having
this option set followed by nothing else doesn't provide anything.
Remove these stanzas.

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