libtool 1.3.5 patches for AIX

[mcnichol]

I've got a bunch of changes to submit for AIX.

Currently I just have patches for 1.3.5, but I'll be doing the
same thing for 1.4 when I have a little more time.

The changes include the following:

- Adding support for the latest version of AIX (version 5.0).
- Adding support for AIX on IA64 (which uses a SYSV type linker).
- Adding support for run time linking on AIX POWER.
  This feature is set up so that it is only turned on when -brtl is
  detected in LD_FLAGS.  Otherwise the old (strange) AIX linking is used.
- Building standard shared libraries on AIX POWER more like the
  rest of the system libraries where the shared object is archived 
  lib<xxx>.a
- Remove support for -bexpall flag because it does bad things.
- Fix a quote problem around -berok flag.

Dan