Log Message:
asm6809: Import version 2.12 into pkgsrc cross.

asm6809 is a portable cross assembler targeting the Motorola 6809
and Hitachi 6309.

Features arbitrarily complex expressions (with most C-style
operators available), forward references, macro expansion and
conditional assembly.  Output formats are: Raw binary, DragonDOS
binary, CoCo RS-DOS (or "DECB") binary, Motorola SREC, Intel HEX.