bp2build: arch-configurable selects for label list attrs.

This CL adds the configurable LabelListAttribute support to bp2build.

Test: go test
Change-Id: I2ef9e385d9cf1b1845988128eca1d8cda1ecb5e8
diff --git a/cc/library_headers.go b/cc/library_headers.go
index 719d538..8286848 100644
--- a/cc/library_headers.go
+++ b/cc/library_headers.go
@@ -62,9 +62,9 @@
 }
 
 type bazelCcLibraryHeadersAttributes struct {
-	Hdrs     bazel.LabelList
-	Includes bazel.LabelList
-	Deps     bazel.LabelList
+	Hdrs     bazel.LabelListAttribute
+	Includes bazel.LabelListAttribute
+	Deps     bazel.LabelListAttribute
 }
 
 type bazelCcLibraryHeaders struct {