Detect the runtime linker's search path and add to the compile time
linker's search path. This is needed because OpenBSD's static linker
does not search for shared library dependencies in the same places as
the runtime linker.
OpenBSD shared libraries use a ".so.<major>.<minor>" extension and do
not have a symlink with just a ".so" extension. Its "ld" is capable of
finding the library with the best version. This change adds support for
finding such libraries. See issue #3470.
Chuck Atkins
Brad King
Bill Hoffman