Heads up: dropping mkinitrd from joyride, might break stuff

[Daniel Drake]

Hi,

mkinitrd is currently included in our builds but we don't need it. It
brings in some other unneeded dependencies too, which have grown a bit
for F9.

We're going to try removing it. Apparently last time this was tried,
several essential components fell out of the build, and I guess this
might happen again.

I'm in charge of fixing any breakage here - I'll readd the important
stuff through pilgrim as quickly as I can, but there might be a broken
joyride build or 2 today.

Daniel