buildroot

minnowboard_max-graphical: increase ext4 filesystem size

Now we have changed the default ext2/3/4 filesystem size from automatic
to 60MB, the minnowboard_max graphical demo config doesn't fit anymore.
So increase it to double.

The exact number doesn't matter much, it has to be somewhat smaller
than 128MiB, so let's take a round number of 120000K.

Signed-off-by: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>