add support for split debuginfo files

There seem to be a few variations on the tools and arguments
available for creating split debuginfo files.
I used the following:

objcopy --only-keep-debug libjulia.so libjulia.so.debug
strip -g libjulia.so
objcopy --add-gnu-debuglink=libjulia.so.debug libjulia.so

(cherry picked from commit b67fd06)
ref #17962