bug#22435: Need improvement in `stat` command's file-system type output

[D.P.Pandya]

If I tries to check filesystem type by `stat -f` command on my Ext4 
partition, it gives output: ext2/ext3 which is wrong.

Example:

$ df -T /
Filesystem     Type 1K-blocks     Used Available Use% Mounted on
/dev/sda8      ext4  25672796 10813104  13532596  45% /

But `stat` shows incorrectly ext2/ext3

$ stat -f -c %T /
ext2/ext3

So, the output for filesystem type by `stat` command should be 
improved/fixed.

Thanks