tools/ceph_objecstore_tool: cleanup collection handle on exit

Signed-off-by: Pere Diaz Bou <[email protected]>

Author: pereman2

src/tools/ceph_objectstore_tool.cc

@@ -4742,6 +4742,7 @@ int main(int argc, char **argv)
     cout <<  ostr.str() << std::endl;
   }
 
+  ch.reset(nullptr);
   int r = mount_readonly ? fs->umount_readonly() : fs->umount();
   if (r < 0) {
     cerr << "umount failed: " << cpp_strerror(r) << std::endl;