* targets.c, config/i960-bout.mt, hosts/*: added
HOST_BIG_ENDIAN_DEFAULT_VECTOR and
HOST_LITTLE_ENDIAN_DEFAULT_VECTOR because bout archive format
depends on the endianness of the host. Added #define
HOST_BIG_ENDIAN_P and #undef HOST_BIG_ENDIAN_P to a number of
configuration files in hosts/ (it was already in some).