bpo-37085: Expose SocketCAN bcm_msg_head flags (#13646)

Expose the CAN_BCM SocketCAN constants used in the bcm_msg_head struct
flags (provided by <linux/can/bcm.h>) under the socket library.

This adds the following constants with a CAN_BCM prefix:

  * SETTIMER
  * STARTTIMER
  * TX_COUNTEVT
  * TX_ANNOUNCE
  * TX_CP_CAN_ID
  * RX_FILTER_ID
  * RX_CHECK_DLC
  * RX_NO_AUTOTIMER
  * RX_ANNOUNCE_RESUME
  * TX_RESET_MULTI_IDX
  * RX_RTR_FRAME
  * CAN_FD_FRAME

The CAN_FD_FRAME flag was introduced in the 4.8 kernel, while the other
ones were present since SocketCAN drivers were mainlined in 2.6.25. As
such, it is probably unnecessary to guard against these constants being
missing.
diff --git a/Misc/ACKS b/Misc/ACKS
index e02e8e1..9ff74ec 100644
--- a/Misc/ACKS
+++ b/Misc/ACKS
@@ -397,6 +397,7 @@
 Toby Dickenson
 Mark Dickinson
 Jack Diederich
+Karl Ding
 Daniel Diniz
 Humberto Diogenes
 Yves Dionne