make_chroot: drop cross-compiler install

Since our tooling can install the required toolchains on demand for a
board, there's no need for the initial sdk creation to install all of
them.

BUG=chromium:342199
TEST=`cbuildbot chromiumos-sdk` passes
TEST=created a new chroot, saw no cross-compilers, built x86-generic board,
     and saw the toolchain get installed
CQ-DEPEND=CL:227232, CL:228271, CL:227671

Change-Id: Ic91bf54ec73bdff8d5a501a5321a2418b5b5f97a
Reviewed-on: https://chromium-review.googlesource.com/227672
Reviewed-by: Bertrand Simonnet <bsimonnet@chromium.org>
Tested-by: Mike Frysinger <vapier@chromium.org>
Commit-Queue: Mike Frysinger <vapier@chromium.org>
1 file changed