When building the ramdisk we don't cleanup the temporary
directories after ourselves. This leaves /tmp/image.* directories
mounted and /tmp/image.* directories on the system.
Also the ramdisk-functions duplicate, from what I can see,
the cleanup function from common-functions. So when a job
is killed off it ends up leaving /tmp/image.* directories
on the system.
Change-Id: I2d73aabd0eb176027b4e7368580db08902e2b6ab