fbdev: omapfb: remove unused board support

A number of omap1 based board files got removed, so the corresponding
framebuffer drivers are no longer used. The remaining ones are for
ams_delta, osk and palmTE, which are still part of the mainline kernel.

Cc: Aaro Koskinen <aaro.koskinen@iki.fi>
Cc: Janusz Krzysztofik <jmkrzyszt@gmail.com>
Cc: linux-omap@vger.kernel.org
Cc: Marek Vasut <marek.vasut@gmail.com>
Cc: Angelo Arrifano <miknix@gmail.com>
Cc: Imre Deak <imre.deak@intel.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>