these were added when arm fdpic support was upstreamed in gcc. one patch
was just entirely wrong (broke arm init/fini arrays, gcc pr#114158) and
the other put arm-specific unwind logic in place for all fdpic targets
and broke building of the unwinder code.
this directory uses relative pathnames to access libgcc unwind
headers, but with cowpatch, those are relative to the libstdc++-v3
directory in the unpatched tree unless libstdc++-v3 has been
cow-split.
this calls for a general solution at some point, but for now, just add
an explicit dummy patch to trigger cow splitting.