Update kernel headers to v3.14.

Other changes:
- Modify update_all.py to skip ion header files when importing into aosp.
- Fix generate_uapi_headers.sh to handle imports from a linux-stable kernel.

Change-Id: I1ad81b9ccb063c21740f9875f2cc1238052cd4b3

libc/kernel/uapi/asm-mips/asm/socket.h

@@ -84,5 +84,8 @@
 #define SO_NOFCS 43
 #define SO_LOCK_FILTER 44
 #define SO_SELECT_ERR_QUEUE 45
-#endif
+#define SO_BUSY_POLL 46
 /* WARNING: DO NOT EDIT, AUTO-GENERATED CODE - SEE TOP FOR INSTRUCTIONS */
+#define SO_MAX_PACING_RATE 47
+#define SO_BPF_EXTENSIONS 48
+#endif