evita: remove non-CM/CWM configurations

TWRP is a separate project. Really, we need to abide by the "eat your own
dogfood" philosophy anyways and use CWM to motivate improving it.

Note: although TARGET_RECOVERY_PIXEL_FORMAT is not TWRP specific, it is
already defined in s4-common.

Change-Id: I50b8ae1bd6bd5165b3bd9d7b075ba6d906eb9c28