uboot-imx

fs: Add fs_get_type_name to return current filesystem name

Add fs_get_type_name so we can get the current filesystem type.

Signed-off-by: Alex Kiernan <alex.kiernan@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Joe Hershberger <joe.hershberger@ni.com>