[patch] RS/6000 fixes

[Hidvegi]

Geoff Keating wrote:
> AIX as doesn't strictly enforce the -m flags.  To be sure, you need to
> find an as that doesn't understand any non-power opcodes, and see if
> it understands 'crnot'.

What's wrong just accepting these in power mode?  These are just
extended mnemonics for common mode instructions.  The AIX assembler
accepts them, so it is not a compatibility problem, and the binary
will work on power.

Zoli