aco: stop scheduling at p_logical_end

No Foz-DB changes, but this fixes some issues when the spiller inserts
scratch loads after p_logical_end for p_return.

Reviewed-by: Daniel Schürmann <daniel@schuermann.dev>

Cc: mesa-stable
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/27119>
(cherry picked from commit 74fc2e287f)

.pick_status.json

@@ -674,7 +674,7 @@
         "description": "aco: stop scheduling at p_logical_end",
         "nominated": true,
         "nomination_type": 0,
-        "resolution": 0,
+        "resolution": 1,
         "main_sha": null,
         "because_sha": null,
         "notes": null

src/amd/compiler/aco_scheduler.cpp

@@ -1087,6 +1087,9 @@ schedule_block(sched_ctx& ctx, Program* program, Block* block, live& live_vars)
    for (unsigned idx = 0; idx < block->instructions.size(); idx++) {
       Instruction* current = block->instructions[idx].get();
 
+      if (current->opcode == aco_opcode::p_logical_end)
+         break;
+
       if (block->kind & block_kind_export_end && current->isEXP() && ctx.schedule_pos_exports) {
          unsigned target = current->exp().dest;
          if (target >= V_008DFC_SQ_EXP_POS && target < V_008DFC_SQ_EXP_PRIM) {