make_chroot: don't enable git-prompt via bashcomp
make_chroot: don't enable git-prompt via bashcomp

Newer git ebuilds have decided that the "git-prompt" script isn't really
bash completion so stopped installing it via that mechanism. Instead it
installed it started installing it in /usr/share/docs which gets
compressed by default and the path is based on ebuild version. The path
changed again in 1.9.3 to /usr/share/git and didn't compress it so that
makes it actually possibly usable but 1.9.3 or later isn't stable yet.

We can re-enable it the next time git gets updated but not worth fussing
over the current brokenness right now.

mjg59/scripts,BugRoger/scripts,fivethreeo/scripts,andrejro/coreos--scripts,mjg59/scripts,smilart/scripts,gtank/scripts,andrejro/coreos--scripts,mjg59/scripts,mischief/scripts,sigma/coreos-scripts,glevand/coreos--scripts,marineam/coreos-scripts,trnubo/scripts,sigma/coreos-scripts,marineam/coreos-scripts,gtank/scripts,nicescale/scripts,glevand/coreos--scripts,nicescale/scripts,zhang0137/scripts,endocode/scripts,trnubo/scripts,smilart/scripts,zhang0137/scripts,fivethreeo/scripts,endocode/scripts,marineam/coreos-scripts,mischief/scripts,endocode/scripts,BugRoger/scripts,vmware/coreos-scripts,mischief/scripts,BugRoger/scripts,coreos/scripts,nicescale/scripts,coreos/scripts,vmware/coreos-scripts,sigma/coreos-scripts,zhang0137/scripts,smilart/scripts,trnubo/scripts,vmware/coreos-scripts,andrejro/coreos--scripts,gtank/scripts,fivethreeo/scripts