[zircon] [gn] Produce legacy board list files

Bug: BLD-325
Bug: BLD-353
Test: gn gen && ninja, manual inspection of board-*.list files
Change-Id: I3f06359c07b1021868d743f26b3edcfc7fb9f37f
diff --git a/zircon/BUILD.gn b/zircon/BUILD.gn
index aed278f..6957906 100644
--- a/zircon/BUILD.gn
+++ b/zircon/BUILD.gn
@@ -140,6 +140,17 @@
         "$zx/system/fidl/fuchsia-tracelink",
       ]
     }
+
+    generated_file("boards-$cpu.list") {
+      testonly = true
+      outputs = [
+        "$root_build_dir/export/$target_name",
+      ]
+      data_keys = [ "legacy_pkg_boards" ]
+      deps = [
+        ":$cpu",
+      ]
+    }
   }
 }
 
diff --git a/zircon/system/dev/board/gauss/BUILD.gn b/zircon/system/dev/board/gauss/BUILD.gn
index e5a5bee..bd32863 100644
--- a/zircon/system/dev/board/gauss/BUILD.gn
+++ b/zircon/system/dev/board/gauss/BUILD.gn
@@ -29,6 +29,12 @@
   data_deps = [
     ":gauss-i2c-test",
   ]
+
+  # TODO(BLD-353): Temporary hacks for integrating with the legacy Fuchsia
+  # GN build.
+  metadata = {
+    legacy_pkg_boards = [ target_name ]
+  }
 }
 
 driver("gauss-i2c-test") {
diff --git a/zircon/system/dev/board/hikey960/BUILD.gn b/zircon/system/dev/board/hikey960/BUILD.gn
index 2cabe00..2f7ae4a 100644
--- a/zircon/system/dev/board/hikey960/BUILD.gn
+++ b/zircon/system/dev/board/hikey960/BUILD.gn
@@ -28,6 +28,12 @@
     "$zx/kernel/target/arm64/boot-shim:hikey960",
     ":hi3660-i2c-test",  # TODO: only for test configs
   ]
+
+  # TODO(BLD-353): Temporary hacks for integrating with the legacy Fuchsia
+  # GN build.
+  metadata = {
+    legacy_pkg_boards = [ target_name ]
+  }
 }
 
 driver("hi3660-i2c-test") {
diff --git a/zircon/system/dev/board/imx8mevk/BUILD.gn b/zircon/system/dev/board/imx8mevk/BUILD.gn
index bf58af8..b0e742d 100644
--- a/zircon/system/dev/board/imx8mevk/BUILD.gn
+++ b/zircon/system/dev/board/imx8mevk/BUILD.gn
@@ -27,4 +27,10 @@
   data_deps = [
     "$zx/kernel/target/arm64/boot-shim:imx8mevk",
   ]
+
+  # TODO(BLD-353): Temporary hacks for integrating with the legacy Fuchsia
+  # GN build.
+  metadata = {
+    legacy_pkg_boards = [ target_name ]
+  }
 }
diff --git a/zircon/system/dev/board/qemu/BUILD.gn b/zircon/system/dev/board/qemu/BUILD.gn
index eae72c8..c3b0b30 100644
--- a/zircon/system/dev/board/qemu/BUILD.gn
+++ b/zircon/system/dev/board/qemu/BUILD.gn
@@ -17,5 +17,11 @@
     data_deps = [
       "$zx/kernel/target/arm64/boot-shim:qemu",
     ]
+
+    # TODO(BLD-353): Temporary hacks for integrating with the legacy Fuchsia
+    # GN build.
+    metadata = {
+      legacy_pkg_boards = [ target_name ]
+    }
   }
 }
diff --git a/zircon/system/dev/board/vim/BUILD.gn b/zircon/system/dev/board/vim/BUILD.gn
index 8de44ca..6be166c 100644
--- a/zircon/system/dev/board/vim/BUILD.gn
+++ b/zircon/system/dev/board/vim/BUILD.gn
@@ -41,4 +41,10 @@
     "$zx/system/ulib/zx",
     "$zx/system/ulib/zxcpp",
   ]
+
+  # TODO(BLD-353): Temporary hacks for integrating with the legacy Fuchsia
+  # GN build.
+  metadata = {
+    legacy_pkg_boards = [ "vim2" ]
+  }
 }
diff --git a/zircon/system/dev/board/x86/BUILD.gn b/zircon/system/dev/board/x86/BUILD.gn
index efe5ea8..7aa95a5 100644
--- a/zircon/system/dev/board/x86/BUILD.gn
+++ b/zircon/system/dev/board/x86/BUILD.gn
@@ -82,4 +82,10 @@
     "$zx/third_party/lib/acpica",
     "$zx/third_party/ulib/chromiumos-platform-ec",
   ]
+
+  # TODO(BLD-353): Temporary hacks for integrating with the legacy Fuchsia
+  # GN build.
+  metadata = {
+    legacy_pkg_boards = [ "pc" ]
+  }
 }