cpu-minor: Get rid of the MinorDynInst::init function.

Just initialize the global MinorDynInst::bubbleInst with a lambda to
avoid having a init() function somebody needs to remember to call, and
which needs to only be called once (or which should only do something
once).

Change-Id: Ied6397e52ccefd6e6bdca012a01f004a47d6f26e
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/53583
Maintainer: Gabe Black <gabe.black@gmail.com>
Reviewed-by: Bobby Bruce <bbruce@ucdavis.edu>
Tested-by: kokoro <noreply+kokoro@google.com>
3 files changed