[LMDB] ITS#9376 Fixes for repeated deletes with xcursor
Issue reported in https://github.com/erthink/libmdbx/issues/121, patch based on https://github.com/erthink/libmdbx/commit/daf37363b4bca091aaafc7ee52585f1708b2f82a
Needs a test case.
Edited by Howard Chu