[PATCH, rs6000] Add non-relative jump table support for 64bit rs6000

[HAO CHEN GUI via Gcc-patches]

David,

Seems there is something wrong with my email box.  I lost your email. I 
reconfigured the box and it should be OK now.

Could you inform me how to exclude AIX from the condition testing? By 
the ABI? Thanks a lot.

Haochen Gui