TARGET_BYTE_ORDER_SELECTABLE_P): Replace TARGET_BYTE_ORDER and TARGET_BYTE_ORDER_SELECTABLE.
config files moved to an appropriate config/<cpu> subdirectory. * nm-*, xm-*, tm-*: All native, host, and target files, which get linked to nm.h, xm.h, and tm.h respectively by configure, moved to appropriate config/<cpu> subdirectory.