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/asm-x86/asm/ldt.h b/libc/kernel/uapi/asm-x86/asm/ldt.h
index ff88760..c901fee 100644
--- a/libc/kernel/uapi/asm-x86/asm/ldt.h
+++ b/libc/kernel/uapi/asm-x86/asm/ldt.h
@@ -23,20 +23,20 @@
 /* WARNING: DO NOT EDIT, AUTO-GENERATED CODE - SEE TOP FOR INSTRUCTIONS */
 #ifndef __ASSEMBLY__
 struct user_desc {
- unsigned int entry_number;
- unsigned int base_addr;
+  unsigned int entry_number;
+  unsigned int base_addr;
 /* WARNING: DO NOT EDIT, AUTO-GENERATED CODE - SEE TOP FOR INSTRUCTIONS */
- unsigned int limit;
- unsigned int seg_32bit:1;
- unsigned int contents:2;
- unsigned int read_exec_only:1;
+  unsigned int limit;
+  unsigned int seg_32bit : 1;
+  unsigned int contents : 2;
+  unsigned int read_exec_only : 1;
 /* WARNING: DO NOT EDIT, AUTO-GENERATED CODE - SEE TOP FOR INSTRUCTIONS */
- unsigned int limit_in_pages:1;
- unsigned int seg_not_present:1;
- unsigned int useable:1;
+  unsigned int limit_in_pages : 1;
+  unsigned int seg_not_present : 1;
+  unsigned int useable : 1;
 #ifdef __x86_64__
 /* WARNING: DO NOT EDIT, AUTO-GENERATED CODE - SEE TOP FOR INSTRUCTIONS */
- unsigned int lm:1;
+  unsigned int lm : 1;
 #endif
 };
 #define MODIFY_LDT_CONTENTS_DATA 0