reorg.c (fill_slots_from_thread): Reinstate code typoed out in "Remove CC0".

reorg.c (fill_slots_from_thread): Reinstate code typoed out in "Remove CC0".

The typo here, is obviously mistaken removal of lines next
to a line that was validly removed.  Targets affected are
those with a delay-slot *and* defining TARGET_FLAGS_REGNUM.
In-tree, a git-grep says the only ones matching are CRIS,
h8300 and visium.  The code removal has the effect of
wrong-code, not reverting the effect of r11-2814.

I'm "guessing" it was the effect of an incorrect conflict
resolution in preparatory work for the r12-440 /
bd1cd0d0e0fe / "Remove CC0" commit, when rebasing a related
branch, and not testing any of the affected targets.  Either
way, the effect was a btest-gcc.sh state of "regress-1152"
for cris-elf.  FWIW, I wrote the removed code (sans the
validly removed cc0 line), a part of what was committed at
2020-08-24 as 0e6c51de8ec47 / r11-2814.

This commit gets cris-elf test-results back to a sane state
(tested at 0ffdbc85d9a6 / r12-761).

gcc:
	* reorg.c (fill_slots_from_thread): Reinstate code typoed out in
	"Remove CC0".