[PATCH] Fixup __glibcpp_long_double_bits to 64 for PPC

[Franz Sirl]

Hi,

as discussed. Bootstrapped the branch on powerpc-linux-gnu without 
regressions.

OK to commit to mainline and branch?

Franz.

        * configure.target: Set LIMITSH for powerpc-*-*.
        * config/cpu/powerpc/bits/limits.h: New file.