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/nfs_idmap.h b/libc/kernel/uapi/linux/nfs_idmap.h
index 039bf40..5f5c0eb 100644
--- a/libc/kernel/uapi/linux/nfs_idmap.h
+++ b/libc/kernel/uapi/linux/nfs_idmap.h
@@ -32,12 +32,12 @@
 #define IDMAP_STATUS_SUCCESS 0x08
 /* WARNING: DO NOT EDIT, AUTO-GENERATED CODE - SEE TOP FOR INSTRUCTIONS */
 struct idmap_msg {
- __u8 im_type;
- __u8 im_conv;
- char im_name[IDMAP_NAMESZ];
+  __u8 im_type;
+  __u8 im_conv;
+  char im_name[IDMAP_NAMESZ];
 /* WARNING: DO NOT EDIT, AUTO-GENERATED CODE - SEE TOP FOR INSTRUCTIONS */
- __u32 im_id;
- __u8 im_status;
+  __u32 im_id;
+  __u8 im_status;
 };
 #endif
 /* WARNING: DO NOT EDIT, AUTO-GENERATED CODE - SEE TOP FOR INSTRUCTIONS */