font: unifont: compress binary data and link via ld directly

font: unifont: compress binary data and link via ld directly

Instead of using the blown up UTERM_FORMAT_GREY binary data, we now use an
A1 1bit alpha channel and extract the data during runtime. This guarantees
that only used characters will be extracted into the full alpha channel.

We should add support for A1 formats in uterm to avoid this problem
entirely.

We also now link the binary file directly into the module via ld. This
avoids the long compile times for the huge C-array that we previously
generated. As a side effect, you no longer run out of memory linking this
file on small machines.

With this change we could even start making unifont a default font-backend
as it now works pretty well.

Signed-off-by: David Herrmann <dh.herrmann@googlemail.com>