Refactor the initrd_inject methods.
Refactor the initrd_inject methods.

This just breaks them down into smaller chunks that are
easier to read.  There should be no change in functionality.

Signed-off-by: Chris Lalancette <281cd07d7578d97c83271fbbf2faddb83ab3791c@gmail.com>

ndonegan/oz,mgagne/oz,imcleod/oz,clalancette/oz,moofrank/oz,clalancette/oz,nullr0ute/oz,moofrank/oz,cernops/oz,imcleod/oz,cernops/oz,ndonegan/oz,mgagne/oz,NeilBryant/oz,nullr0ute/oz,NeilBryant/oz