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/fcntl.h b/libc/kernel/uapi/linux/fcntl.h
index 02cc869..b888dc9 100644
--- a/libc/kernel/uapi/linux/fcntl.h
+++ b/libc/kernel/uapi/linux/fcntl.h
@@ -24,7 +24,7 @@
 #define F_GETLEASE (F_LINUX_SPECIFIC_BASE + 1)
 #define F_CANCELLK (F_LINUX_SPECIFIC_BASE + 5)
 #define F_DUPFD_CLOEXEC (F_LINUX_SPECIFIC_BASE + 6)
-#define F_NOTIFY (F_LINUX_SPECIFIC_BASE+2)
+#define F_NOTIFY (F_LINUX_SPECIFIC_BASE + 2)
 /* WARNING: DO NOT EDIT, AUTO-GENERATED CODE - SEE TOP FOR INSTRUCTIONS */
 #define F_SETPIPE_SZ (F_LINUX_SPECIFIC_BASE + 7)
 #define F_GETPIPE_SZ (F_LINUX_SPECIFIC_BASE + 8)
@@ -44,7 +44,7 @@
 #define DN_RENAME 0x00000010
 #define DN_ATTRIB 0x00000020
 #define DN_MULTISHOT 0x80000000
-#define AT_FDCWD -100
+#define AT_FDCWD - 100
 /* WARNING: DO NOT EDIT, AUTO-GENERATED CODE - SEE TOP FOR INSTRUCTIONS */
 #define AT_SYMLINK_NOFOLLOW 0x100
 #define AT_REMOVEDIR 0x200