TARGET_BIG_ENDIAN is now completely dead, except where it was
originally supposed to be used (internally in the toolchain building).
TARGET_ARCH has changed in three cases:
(1) Little endian mips has changed to mipsel.
(2) Big endian mips has changed to mipseb.
(3) Big endian arm has changed to armeb.
Some additional changes are needed to make 'make universe' work on arm
and mips after this change, so those are commented out for now.
UPDATING information will be forthcoming. Any remaining rough edges
will be hammered out in -current.
e8dce5b9b3