shader: count only register writes in the callee link check

The check that a native callee keeps its link register read bits 16-23
of every instruction as a destination. RET was exempt, but BRA, NOP and
ISETP/FSETP (which write predicates) also have zero there, so callees
with an R0 link that compare or branch were rejected. IMAD.WIDE writes a
register pair, so its second register now counts as well.

Assisted-by: Claude Opus 5.5 (debugging, implementation and drafting)
Signed-off-by: Duck912 <350528965+Duck912@users.noreply.github.com>

0 files changed, 0 insertions, 0 deletions