Upgrade kernel headers to 3.18.10.

Change-Id: Iff1f1c830780585990856a5114b559c61282dcd6
diff --git a/libc/kernel/uapi/linux/version.h b/libc/kernel/uapi/linux/version.h
index cb6842a..a6c6a2f 100644
--- a/libc/kernel/uapi/linux/version.h
+++ b/libc/kernel/uapi/linux/version.h
@@ -16,5 +16,5 @@
  ***
  ****************************************************************************
  ****************************************************************************/
-#define LINUX_VERSION_CODE 201219
+#define LINUX_VERSION_CODE 201226
 #define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) + (c))