It seems that the /mnt/tftp was copied from the defaultenv-2. The
defaultenv-2 got a update to make it more robust by enabling all
interfaces. During this sync I added a entry to support automount for
/mnt/nfs mountpoint.

Cc: Stefan Christ <s.christ@phytec.de>
Signed-off-by: Marco Felsch <m.felsch@pengutronix.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

The *-menu-add-entry functions no longer exist in defaultenv-2, so
remove the calls to these functions.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

For the phyCORE-i.MX6 add an automount command for the first partition
on the eMMC device.

Signed-off-by: Stefan Christ <s.christ@phytec.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

The extra environment folder for the phyCORE-i.MX6 had the suffix
'-mira'. That's the name of a baseboard. Since the bootloader is generic
for all baseboards, use a generic suffix for the environment folder.

Signed-off-by: Stefan Christ <s.christ@phytec.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>