aco/isel: move visit_alu_instr() into separate file

Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/34977>

src/amd/compiler/instruction_selection/aco_instruction_selection.h

@@ -248,6 +248,9 @@ void finish_program(isel_context* ctx);
 void _isel_err(isel_context* ctx, const char* file, unsigned line, const nir_instr* instr,
                const char* msg);
 
+/* aco_select_nir_alu.cpp */
+void visit_alu_instr(isel_context* ctx, nir_alu_instr* instr);
+
 } // namespace aco
 
 #endif /* ACO_INSTRUCTION_SELECTION_H */

src/amd/compiler/meson.build

@@ -35,6 +35,7 @@ libaco_files = files(
   'instruction_selection/aco_isel_cfg.cpp',
   'instruction_selection/aco_isel_helpers.cpp',
   'instruction_selection/aco_isel_setup.cpp',
+  'instruction_selection/aco_select_nir_alu.cpp',
   'instruction_selection/aco_select_nir.cpp',
   'instruction_selection/aco_select_ps_epilog.cpp',
   'instruction_selection/aco_select_ps_prolog.cpp',