Start mn10200 gdb port by adding copies of mn10300
target-specific files with all instances of mn10300 changed
to mn10200 to start with.
* mn10200-tdep.c: new
* config/mn10200/tm-mn10200.h: new, REGISTER_SIZE is 24 bits not 32,
SP_REGNUM and FP_REGNUM are different, also no lar or lir.
* config/mn10200/mn10200.mt: new