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/net.h b/libc/kernel/uapi/linux/net.h
index 0dc1481..0efb68f 100644
--- a/libc/kernel/uapi/linux/net.h
+++ b/libc/kernel/uapi/linux/net.h
@@ -48,12 +48,12 @@
 /* WARNING: DO NOT EDIT, AUTO-GENERATED CODE - SEE TOP FOR INSTRUCTIONS */
 #define SYS_SENDMMSG 20
 typedef enum {
- SS_FREE = 0,
- SS_UNCONNECTED,
+  SS_FREE = 0,
+  SS_UNCONNECTED,
 /* WARNING: DO NOT EDIT, AUTO-GENERATED CODE - SEE TOP FOR INSTRUCTIONS */
- SS_CONNECTING,
- SS_CONNECTED,
- SS_DISCONNECTING
+  SS_CONNECTING,
+  SS_CONNECTED,
+  SS_DISCONNECTING
 } socket_state;
 /* WARNING: DO NOT EDIT, AUTO-GENERATED CODE - SEE TOP FOR INSTRUCTIONS */
 #define __SO_ACCEPTCON (1 << 16)