Add Linux Aarch 64 support

WIP

Author: grav

deps/BUILD.bazel

@@ -58,6 +58,7 @@ depsgen(
     name = "prebuilt_protoc",
     deps = [
         ":prebuilt_protoc_linux",
+        ":prebuilt_protoc_linux_aarch64",
         ":prebuilt_protoc_osx",
         ":prebuilt_protoc_windows",
     ],
@@ -317,6 +318,21 @@ filegroup(
     urls = ["https://github.com/google/protobuf/releases/download/v3.20.1/protoc-3.20.1-linux-x86_64.zip"],
 )
 
+
+proto_dependency(
+    name = "prebuilt_protoc_linux_aarch64",
+    build_file_content = """
+filegroup(
+    name = "protoc",
+    srcs = ["bin/protoc"],
+    visibility = ["//visibility:public"],
+)
+""",
+    repository_rule = "http_archive",
+    sha256 = "3a0e900f9556fbcac4c3a913a00d07680f0fdf6b990a341462d822247b265562",
+    urls = ["https://github.com/google/protobuf/releases/download/v3.20.1/protoc-3.20.1-linux-aarch_64.zip"],
+)
+
 proto_dependency(
     name = "prebuilt_protoc_osx",
     build_file_content = """

toolchain/BUILD.bazel

@@ -36,6 +36,9 @@ genrule(
         "@bazel_tools//src/conditions:windows": [
             "@prebuilt_protoc_windows//:protoc",
         ],
+        "@bazel_tools//src/conditions:linux_aarch64": [
+            "@prebuilt_protoc_linux_aarch64//:protoc",
+        ],
         "//conditions:default": [
             "@prebuilt_protoc_linux//:protoc",
         ],