Switch kernel header parsing to python libclang

Replace the tokenizer in cpp.py with libclang.

Bug: 18937958
Change-Id: I27630904c6d2849418cd5ca3d3c612ec3078686d
diff --git a/libc/kernel/uapi/linux/atm_he.h b/libc/kernel/uapi/linux/atm_he.h
index c62f456..809ac61 100644
--- a/libc/kernel/uapi/linux/atm_he.h
+++ b/libc/kernel/uapi/linux/atm_he.h
@@ -27,8 +27,8 @@
 #define HE_REGTYPE_MBOX 4
 /* WARNING: DO NOT EDIT, AUTO-GENERATED CODE - SEE TOP FOR INSTRUCTIONS */
 struct he_ioctl_reg {
- unsigned addr, val;
- char type;
+  unsigned addr, val;
+  char type;
 };
 /* WARNING: DO NOT EDIT, AUTO-GENERATED CODE - SEE TOP FOR INSTRUCTIONS */
 #endif