ARM: pxa: Rename Colibri evalboard

Rename colibri-pxa270-evalboard to colibri-evalboard as this board is used with
all Colibri modules.

Signed-off-by: Marek Vasut <marek.vasut@gmail.com>
Acked-by: Daniel Mack <daniel@caiaq.de>
Signed-off-by: Eric Miao <eric.y.miao@gmail.com>