This reverts commit 89191d6267.
Add a generic implementation of 'ls' using opendir/readdir/closedir, and
replace fat's custom implementation. Other filesystems should move to
the generic implementation after they add opendir/readdir/closedir
support.
Signed-off-by: Vipul Kumar <vipul.kumar@xilinx.com>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>