contrib: don't keep PREFIX/bin in the PATH
And other PREFIX/bin related patches.
PREFIX/bin
contains cross-compiled binaries. It may be binaries native or runnable to the local machine, but they are not supposed to be used, as they are not used when cross-compiling. binaries we want to use are in BUILDPREFIX/bin
aka BUILDBINDIR
. And that one is always added to the PATH in contribs.
Even worse, it had priority over the regular PATH so if you have a native tool and a cross-compiled one, the cross-compiled one would take priority.
Edited by Steve Lhomme