Update to v4.19 kernel headers.

Test: Builds and boots.
Change-Id: I99a9ed79666e143b47f02ca4e59eed94f69b7e4a
(cherry picked from commit a981e2e52e2e95a65fa9c9b6fb16dcb4c83dd576)
diff --git a/libc/kernel/uapi/linux/cec.h b/libc/kernel/uapi/linux/cec.h
index 98892f7..fd0f824 100644
--- a/libc/kernel/uapi/linux/cec.h
+++ b/libc/kernel/uapi/linux/cec.h
@@ -132,6 +132,8 @@
 #define CEC_EVENT_PIN_CEC_HIGH 4
 #define CEC_EVENT_PIN_HPD_LOW 5
 #define CEC_EVENT_PIN_HPD_HIGH 6
+#define CEC_EVENT_PIN_5V_LOW 7
+#define CEC_EVENT_PIN_5V_HIGH 8
 #define CEC_EVENT_FL_INITIAL_STATE (1 << 0)
 #define CEC_EVENT_FL_DROPPED_EVENTS (1 << 1)
 struct cec_event_state_change {