Fix linking on systems without a working stdatomic.h

Fix linking on systems without a working stdatomic.h

Static libraries need to be sorted in a dependency order, with the
most low-level libraries last.  When we added an atomic counter to
util_bug.c in !760, we introduced a dependency from "log" to
"threads".  This didn't show up immediately, since the dependency
only exists when we're emulating atomic operations due to lack of
platform support.

Fixes bug #41076; bugfix on 0.4.9.1-alpha.