Where to add a new bfd_mach

[Aladdin Chang]

hi, 
I am a newbie in binutils and wonderful how to port binutils-2.11.2
to a new mips arch.

I want to add an new bfd_mach_newmips in bfd-in2.h , but the 
source notice that the file bfd-in2.h was GENERATED, don't modify.

Where can I add a new bfd_mach definition and regenerate the bfd-in2.h ?

thanks,

Aladdin