git: optionally build without PDBs
git: optionally build without PDBs

The `cv2pdb` helper requires a working Visual Studio installation, and
it needs to be able to find it, too, which can be tricky to get right.

Let's offer the option to build `mingw-w64-git` without PDBs, by setting
the environment variable `WITHOUT_PDBS` to something non-empty.

Signed-off-by: Johannes Schindelin <53fb8db7833fca1e1746dd8592f61048d350f64c@gmx.de>

dscho/MINGW-packages,git-for-windows/MINGW-packages,git-for-windows/MINGW-packages,dscho/MINGW-packages,dscho/MINGW-packages,dscho/MINGW-packages,dscho/MINGW-packages,git-for-windows/MINGW-packages