Few applications create the dir_$folder$ objects and users can enable
compat_dir if required. This commit reduces readdir latency by 33%.
Also remove notsup_compat_dir from tests since these directories are
never created. Fixes#927. References #1643.
This should improve performance in many situations. s3fs already
enables the stat cache by default so memorizing noobj makes this more
consistent. Fixes#1901.
