call free() two times,and err on

[pt2go]

i have no idea if the file is already close，so i may be call lfs_file_close() two times.
and free() call two times too, this cause an error.
shell we just add one line to bypass ??

static int lfs_file_rawclose(lfs_t *lfs, lfs_file_t *file) {
.....
// clean up memory
if (!file->cfg->buffer) {
lfs_free(file->cache.buffer);
file->cache.buffer = NULL; //+++++++???
}

return err;

}

[geky]

Hi @pt2go, thanks for creating an issue.

This discussion is related: #790

From my perspective these sort of user-protections are out of scope for now. Though given the related discussion maybe they should be added at some point behind a sort of LFS_USERFRIENDLY define or similar.