Load .lo as well.

Some archives contain so called linker objects, with the affectionate
.lo suffic.  For example the musl libc.a will come in that form.  We
still want to load those objects, hence we should not discard them and
look for .lo as well.  Ultimately we might want to fix this proerly by
looking at the file magic.

rts/linker/LoadArchive.c

@@ -461,6 +461,7 @@ static HsInt loadArchive_ (pathchar *path)
         /* TODO: Stop relying on file extensions to determine input formats.
                  Instead try to match file headers. See #13103.  */
         isObject = (thisFileNameSize >= 2 && strncmp(fileName + thisFileNameSize - 2, ".o"  , 2) == 0)
+                || (thisFileNameSize >= 3 && strncmp(fileName + thisFileNameSize - 3, ".lo" , 3) == 0)
                 || (thisFileNameSize >= 4 && strncmp(fileName + thisFileNameSize - 4, ".p_o", 4) == 0)
                 || (thisFileNameSize >= 4 && strncmp(fileName + thisFileNameSize - 4, ".obj", 4) == 0);