[Bug debug/90575] -gsplit-dwarf leaves behind .dwo file in cwd

[sbergman at redhat dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=90575

--- Comment #3 from Stephan Bergmann <sbergman at redhat dot com> ---
Or, to put it differently:  It looks odd that while `gcc -gsplit-dwarf -c
test.c -o /path/test.o` puts test.dwo next to test.o into /path/, `gcc
-gsplit-dwarf test.c -o /path/test` puts it into cwd.