Improve CIL parsing

treble_sepolicy_tests gets very confused by parentheses in comments.

Fix the search for the opening parenthesis of a statement to skip
comments.

And then update a comment that was intended to use parentheses to
actually do so. (Without the parser change, this fails horribly.)

Test: Build
Change-Id: I1e36136e97dd9b8190add29b7f2155a08ea87d80
diff --git a/private/compat/202404/202404.cil b/private/compat/202404/202404.cil
index b93b56a..869deb6 100644
--- a/private/compat/202404/202404.cil
+++ b/private/compat/202404/202404.cil
@@ -1,5 +1,5 @@
-;; This type may or may not already exist in vendor policy. Re-define it here - duplicate
-;; definitions in CIL will be ignored - so we can reference it in 202404.cil.
+;; This type may or may not already exist in vendor policy. Re-define it here (duplicate
+;; definitions in CIL will be ignored) - so we can reference it in 202404.cil.
 (type vendor_hidraw_device)
 (typeattributeset dev_type (vendor_hidraw_device))