Without this, the upgrade procedure from v4.0 failed to preserve
the mac address. This fixes the bug which is explained here below.

What happened is that the new filesystem (v4.1) returns UNKNOWN as
fpga type, because no hwinfo is there.  This UNKNOWN should be turned
into the default type LX240T, so the fpga is programmed and everything
proceeds.

However, "UNKNOWN" is intermixed with the (expected) error message,
so no LX240T is selected and loading fpga fails.

Later, "ifconifg wr0" fails to retrieve the mac address, because no
WR drivers are running, and the generation of hwinfo fails as well.
As a result, after the second reboot (see user manual) there MAC
address for WR interfaces was not preserved.
Signed-off-by: Alessandro Rubini <rubini@gnudd.com>