Update to v4.15 kernel headers.

Test: NA.
Change-Id: Ic06b0506705a46ed11e3b9f212515d34147c8135
diff --git a/original/uapi/linux/input-event-codes.h b/original/uapi/linux/input-event-codes.h
index f4058bd..061fa62 100644
--- a/original/uapi/linux/input-event-codes.h
+++ b/original/uapi/linux/input-event-codes.h
@@ -407,6 +407,7 @@
 #define BTN_TOOL_MOUSE		0x146
 #define BTN_TOOL_LENS		0x147
 #define BTN_TOOL_QUINTTAP	0x148	/* Five fingers on trackpad */
+#define BTN_STYLUS3		0x149
 #define BTN_TOUCH		0x14a
 #define BTN_STYLUS		0x14b
 #define BTN_STYLUS2		0x14c