iwlwifi: mvm: BT Coex - classify packet priority in BT code

This code is really related to BT Coex - move it to the coex
file.
Also - prepare for a FW API change that will happen soon:
Bits 11 and 12 will be allocated for BT priority. Today, we
only have bit 12.

Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
diff --git a/drivers/net/wireless/iwlwifi/mvm/fw-api-tx.h b/drivers/net/wireless/iwlwifi/mvm/fw-api-tx.h
index b674c2a..8e122f3 100644
--- a/drivers/net/wireless/iwlwifi/mvm/fw-api-tx.h
+++ b/drivers/net/wireless/iwlwifi/mvm/fw-api-tx.h
@@ -76,6 +76,8 @@
  * @TX_CMD_FLG_VHT_NDPA: mark frame is NDPA for VHT beamformer sequence
  * @TX_CMD_FLG_HT_NDPA: mark frame is NDPA for HT beamformer sequence
  * @TX_CMD_FLG_CSI_FDBK2HOST: mark to send feedback to host (only if good CRC)
+ * @TX_CMD_FLG_BT_PRIO_POS: the position of the BT priority (bit 11 is ignored
+ *	on old firmwares).
  * @TX_CMD_FLG_BT_DIS: disable BT priority for this frame
  * @TX_CMD_FLG_SEQ_CTL: set if FW should override the sequence control.
  *	Should be set for mgmt, non-QOS data, mcast, bcast and in scan command
@@ -107,6 +109,7 @@
 	TX_CMD_FLG_VHT_NDPA		= BIT(8),
 	TX_CMD_FLG_HT_NDPA		= BIT(9),
 	TX_CMD_FLG_CSI_FDBK2HOST	= BIT(10),
+	TX_CMD_FLG_BT_PRIO_POS		= 11,
 	TX_CMD_FLG_BT_DIS		= BIT(12),
 	TX_CMD_FLG_SEQ_CTL		= BIT(13),
 	TX_CMD_FLG_MORE_FRAG		= BIT(14),