[build] Create a group for light gcc targets.

Bug: v8:13005
Change-Id: I25f44231d936d7b3688898e6941d3877f31fafd3
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3751205
Commit-Queue: Michael Achenbach <machenbach@chromium.org>
Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Auto-Submit: Michael Achenbach <machenbach@chromium.org>
Cr-Commit-Position: refs/heads/main@{#81589}

BUILD.gn

@@ -6200,6 +6200,16 @@ group("v8_clusterfuzz") {
   }
 }
 
+# Targets we ensure work with gcc. The aim is to keep this list small to have
+# a fast overall compile time.
+group("v8_gcc_light") {
+  testonly = true
+
+  deps = [
+    ":d8",
+  ]
+}
+
 group("v8_archive") {
   testonly = true