* invoke.texi (H8/300 Options): Add -ms2600.
        * config/h8300.c (h8300_init_once): Output an error when -ms2600
        is used without -ms.
        * config/h8300.h (TARGET_MAC): New.
        (TARGET_SWITCHES): Add -ms2600 and -mno-s2600.
        (CONDITIONA_REGISTER_USAGE): Disable the mac register on any
        machine other than H8/S2600.
        * config/h8300.md: Accept mac instructions on the H8/S2600 instead
        of the H8/S2000.

From-SVN: r36414