Slow linking with devkit on Linux

While investigating performance with different linkers and linker configuration, we discovered that the devkit linker on Linux (both bfd and gold) were a lot slower than the native linker on Ubuntu. They are both the same version (2.30), so this was puzzling.

The most obvious explanation for such a big difference would be missing compiler optimizations, but why would such a widely used product like binutils not have their compiler flags setup properly for optimization? But, looking at the build logs for binutils for Ubuntu: https://launchpad.net/ubuntu/+source/binutils/2.30-21ubuntu1~18.04/+build/15453713 they are setting CFLAGS="-O2" when running the build for binutils. I tried this for our devkit, and that created a kit with comparable linking performance to the Ubuntu linker.

We should rebuild the current devkit for Linux with this setting to improve daily life for developers. While at it, I will also add --enable-threads which will make it possible for the adventurous to run the gold linker with threads from the devkit.