* mips-tdep.c (mips_ecoff_reg_to_regnum): Rename to
mips_dwarf_dwarf2_ecoff_reg_to_regnum().
(mips_dwarf_dwarf2_ecoff_reg_to_regnum, mips_stab_reg_to_regnum):
Do range checks on register number obtained from debugging info.
(mips_gdbarch_init): Call set_gdbarch_dwarf_reg_to_regnum() and
set_gdbarch_dwarf2_reg_to_regnum(). Adjust call of
set_gdbarch_ecoff_reg_to_regnum() to account for new name of
mapping function.
(do_fp_register_row): Fix typo which caused double type to be
used when attempting to unpack a float.