[HLO Componentization] Create hlo/transforms/ sub-component (Phase II).

This CL takes care of
1. Migrating external projects dependencies from  xla/service --> xla/hlo/transforms

Phase I takes care of
1. Migrating xla/service/<passes> --> xla/hlo/transforms/<passes>
2. Setting up build aliases in xla/service ensuring external dependencies are still satisfied.

PiperOrigin-RevId: 687723365

third_party/xla/xla/service/spmd/shardy/BUILD

@@ -36,14 +36,14 @@ cc_library(
         "//xla:xla_data_proto_cc",
         "//xla/hlo/ir:hlo",
         "//xla/hlo/pass:hlo_pass",
+        "//xla/hlo/transforms:hlo_dce",
+        "//xla/hlo/transforms:tuple_simplifier",
         "//xla/hlo/translate/hlo_to_mhlo:hlo_to_mlir_hlo",
         "//xla/hlo/translate/mhlo_to_hlo:mlir_hlo_to_hlo",
         "//xla/hlo/utils:hlo_sharding_util",
         "//xla/mlir_hlo:mhlo_passes",
         "//xla/service:computation_layout",
-        "//xla/service:hlo_dce",
         "//xla/service:hlo_proto_cc",
-        "//xla/service:tuple_simplifier",
         "//xla/service/llvm_ir:llvm_util",
         "//xla/service/spmd/shardy/mhlo_round_trip:mhlo_export",
         "//xla/service/spmd/shardy/mhlo_round_trip:mhlo_import",

third_party/xla/xla/service/spmd/shardy/shardy_xla_pass.cc

@@ -46,6 +46,8 @@ limitations under the License.
 #include "xla/hlo/ir/hlo_computation.h"
 #include "xla/hlo/ir/hlo_input_output_alias_config.h"
 #include "xla/hlo/ir/hlo_module.h"
+#include "xla/hlo/transforms/simplifiers/hlo_dce.h"
+#include "xla/hlo/transforms/simplifiers/tuple_simplifier.h"
 #include "xla/hlo/translate/hlo_to_mhlo/hlo_to_mlir_hlo.h"
 #include "xla/hlo/translate/mhlo_to_hlo/mlir_hlo_to_hlo.h"
 #include "xla/hlo/utils/hlo_sharding_util.h"
@@ -54,14 +56,12 @@ limitations under the License.
 #include "xla/mlir_hlo/mhlo/transforms/passes.h"
 #include "xla/service/computation_layout.h"
 #include "xla/service/hlo.pb.h"
-#include "xla/service/hlo_dce.h"
 #include "xla/service/llvm_ir/llvm_util.h"
 #include "xla/service/spmd/shardy/constants.h"
 #include "xla/service/spmd/shardy/mhlo_round_trip/mhlo_export.h"
 #include "xla/service/spmd/shardy/mhlo_round_trip/mhlo_import.h"
 #include "xla/service/spmd/shardy/sdy_round_trip/pipelines.h"
 #include "xla/service/spmd/shardy/utils.h"
-#include "xla/service/tuple_simplifier.h"
 #include "xla/shape.h"
 #include "xla/shape_layout.h"
 #include "xla/shape_util.h"