Switch everything to platforms

This patch switches the codebase over from using the "cpu"
mechanism to using bazel platforms. See
https://docs.bazel.build/versions/master/platforms.html for some more
information.

Most of the substantial changes are in //tools. Instead of using
`cc_toolchain_suite` rules, we now use regular `toolchain` rules that
are registered in the WORKSPACE. That also means that bazel now uses
the target platform to select the compiler.

All --cpu=* arguments should now be --config=* arguments. For example,
`--cpu=roborio` should now be `--config=roborio`. The CI script and
all documentation has been updated to reflect that.

The remainder of the changes revolve around tagging all targets with
`target_compatible_with`.  The old mechanism allowed us to specify
repo-wide defaults. The new mechanism does not. That means every
target that didn't have any compatibility specified, now requires
compatibility with `@platforms//os:linux`.

I used buildozer for the vast majority of `target_compatible_with`
changes. buildozer automatically buildifies any BUILD files it
touches. That means this patch also contains a few non-functional
changes that I was too lazy to remove.

Change-Id: I66d6e6ad9161520ee397597cdb492585820a3acd
diff --git a/y2016/vision/tools/BUILD b/y2016/vision/tools/BUILD
index edbfca5..62ed6b4 100644
--- a/y2016/vision/tools/BUILD
+++ b/y2016/vision/tools/BUILD
@@ -1,12 +1,13 @@
 load("//tools/build_rules:gtk_dependent.bzl", "gtk_dependent_cc_binary", "gtk_dependent_cc_library")
+load("//tools:platforms.bzl", "platforms")
 
 gtk_dependent_cc_binary(
     name = "blob_stream_replay",
     srcs = ["blob_stream_replay.cc"],
-    restricted_to = [
-        "//tools:k8",
-        "//tools:armhf-debian",
-    ],
+    target_compatible_with = platforms.any_of([
+        "@platforms//cpu:x86_64",
+        "//tools/platforms/hardware:raspberry_pi",
+    ]),
     deps = [
         "//aos/vision/blob:range_image",
         "//aos/vision/blob:stream_view",