Build oak_restricted_kernel_bin with Bazel - for bare metal only.

Also, remove toolchain definition no longer needed as we can declare it with aspect gcc.

BUG: 334871992
Change-Id: Ic59b714cc68536377dc1732cd153adb14765d5c1

WORKSPACE

@@ -298,21 +298,19 @@ load("@aspect_gcc_toolchain//toolchain:defs.bzl", "ARCHS", "gcc_register_toolcha
 gcc_register_toolchain(
     name = "gcc_toolchain_x86_64",
     target_arch = ARCHS.x86_64,
+    # target_compatible_with defaults to os:linux.
 )
 
-# --- Rust support ---
-
-load("@rules_cc//cc:repositories.bzl", "rules_cc_dependencies", "rules_cc_toolchains")
-
-rules_cc_dependencies()
-
-rules_cc_toolchains()
-
-register_toolchains(
-    "//bazel/toolchains:x86_64_unknown_none_toolchain",
+gcc_register_toolchain(
+    name = "gcc_toolchain_x86_64_unknown_none",  # Repository @gcc_toolchain_x86_64_unknown_none
+    target_arch = ARCHS.x86_64,
+    target_compatible_with = [
+        "@platforms//cpu:x86_64",
+        "@platforms//os:none",
+    ],
 )
 
-# rules_rust
+# --- Rust support ---
 
 _RUST_NIGHTLY_VERSION = "nightly/2024-02-01"
 

oak_restricted_kernel_bin/BUILD

@@ -0,0 +1,46 @@
+#
+# Copyright 2024 The Project Oak Authors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+
+load("@rules_rust//rust:defs.bzl", "rust_binary")
+
+package(
+    default_visibility = ["//visibility:public"],
+    licenses = ["notice"],
+)
+
+rust_binary(
+    name = "oak_restricted_kernel_bin_virtio_console_channel",
+    srcs = ["src/main.rs"],
+    crate_features = ["virtio_console_channel"],
+    linker_script = "//oak_restricted_kernel:layout.ld",
+    platform = "//:x86_64-unknown-none",
+    deps = [
+        "//oak_linux_boot_params",
+        "//oak_restricted_kernel:oak_restricted_kernel_virtio_console_channel",
+    ],
+)
+
+rust_binary(
+    name = "oak_restricted_kernel_bin_simple_io_channel",
+    srcs = ["src/main.rs"],
+    crate_features = ["simple_io_channel"],
+    linker_script = "//oak_restricted_kernel:layout.ld",
+    platform = "//:x86_64-unknown-none",
+    deps = [
+        "//oak_linux_boot_params",
+        "//oak_restricted_kernel:oak_restricted_kernel_simple_io_channel",
+    ],
+)