GCC 3.3 build on AIX 5.2, done

[Alexy Khrabrov]

I've built GCC 3.3 on AIX 5.2, powerpc 64 bit.

As I indicated earlier, the following aspects
were troublesome:

-- IBM-packaged gcc 2.9-aix51 fails to bootstrap

-- Native cc bootstraps only after 2.5 tweaks,
   the .5 being that the first tweak is two-step:

(1.)  in ../gcc-3.3/gcc/intl/plural.c, remove const
      qualifier of the 2nd parameter in the prototype, pexp.
      (Totally and absurdly, patently wrong, but works(?!))

      bootstrap.

(1.5) put the const back!  proceed.

(2.5) in include/math.h, delete #ifndef __cplusplus..#endif
brackets offending by being after ...\ on the previous line,
thus assumed not at the beginning of the line and mistaken 
for a macro #parameter.

After more than 10 hours of deliberate checking for things,
declaration and linkage, it builds.

Cheers,
Alexy