Get `make check-stage1` working again

Fix #13732.

This is a revised, much less hacky form of PR #13753

The changes here:

 * add instrumentation to aid debugging of linkage errors,
 * fine tune some things in the Makefile where we are telling binaries to use a host-oriented path for finding dynamic libraries, when it should be feeding the binaries a target-oriented path for dynamic libraries.
 * pass along the current stage number to run-make tests, and
 * skip certain tests when running atop stage1.

Fix #13746 as well.