Using flopped pc_if for dataindependent branches

Created by: silabs-oysteink

Flopping pc_if into id_ex_pipe for branches. This is then used as the target for non-taken dataindependent branches. This ensures stability of the branch target for all cycles of a branch in EX, and the pc hardening feature will check pc_if vs the id_ex_pipe.pc_next instead of pc_if vs pc_if as it was.

Signed-off-by: Oystein Knauserud Oystein.Knauserud@silabs.com