nir: change return type to void

init_liveness_block(..) only gets called without using the
always true return value. Switch from bool to void.

Signed-off-by: Christian Gmeiner <christian.gmeiner@gmail.com>
Reviewed-by: Timothy Arceri <tarceri@itsqueeze.com>
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/8051>

src/compiler/nir/nir_liveness.c

@@ -54,7 +54,7 @@ struct live_ssa_defs_state {
 /* Initialize the liveness data to zero and add the given block to the
  * worklist.
  */
-static bool
+static void
 init_liveness_block(nir_block *block,
                     struct live_ssa_defs_state *state)
 {
@@ -67,8 +67,6 @@ init_liveness_block(nir_block *block,
    memset(block->live_out, 0, state->bitset_words * sizeof(BITSET_WORD));
 
    nir_block_worklist_push_head(&state->worklist, block);
-
-   return true;
 }
 
 static bool