[binutils 2.40 branch] backport configure: remove dependencies on gmp and mpfr when gdb is disabled

[Romain GEISSLER]

Hi,

When trying to build binutils 2.40 from the branch I have hit the issue that despite configuring with --disable-gdb --disable-gdbserver the configure file still try to look for gmp and mpfr. Clément Chigot has fixed this issue on the already in the master branch, the patch was posted here https://sourceware.org/pipermail/binutils/2023-January/125430.html and committed as commit 5fb0e308577143ceb313fde5538dc9ecb038f29f.

Can anyone please cherry-pick this commit to the branch 2.40 of the binutils ?

Thanks,
Romain