aco: Fix p_init_scratch for task shaders.

Fixes: d2d94b62f2
Signed-off-by: Timur Kristóf <timur.kristof@gmail.com>
Reviewed-by: Rhys Perry <pendingchaos02@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/18339>
(cherry picked from commit 16c14663e5)

.pick_status.json

@@ -6970,7 +6970,7 @@
         "description": "aco: Fix p_init_scratch for task shaders.",
         "nominated": true,
         "nomination_type": 1,
-        "resolution": 0,
+        "resolution": 1,
         "main_sha": null,
         "because_sha": "d2d94b62f2a4f8686c17b7c33ae02aa2b2029a27"
     },

src/amd/compiler/aco_lower_to_hw_instr.cpp

@@ -2334,7 +2334,7 @@ lower_to_hw_instr(Program* program)
 
                Operand scratch_addr = instr->operands[0];
                Operand scratch_addr_lo(scratch_addr.physReg(), s1);
-               if (program->stage != compute_cs) {
+               if (program->stage.hw != HWStage::CS) {
                   bld.smem(aco_opcode::s_load_dwordx2, instr->definitions[0], scratch_addr,
                            Operand::zero());
                   scratch_addr_lo.setFixed(instr->definitions[0].physReg());