ath10k: QCA9888 hw2.0: add firmware and board files

QCA9888 is a new chip supported by ath10k. Firmware version is 10.4-3.2-00072.
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>
Signed-off-by: Kyle McMartin <kyle@kernel.org>

WHENCE

@@ -2609,6 +2609,10 @@ File: ath10k/QCA9887/hw1.0/board.bin
 File: ath10k/QCA9887/hw1.0/firmware-5.bin
 Version: 10.2.4-1.0-00013
 Licence: ath10k/QCA9887/hw1.0/notice_ath10k_firmware-5.txt
+File: ath10k/QCA9888/hw2.0/board-2.bin
+File: ath10k/QCA9888/hw2.0/firmware-5.bin
+Version: 10.4-3.2-00072
+Licence: ath10k/QCA9888/hw2.0/notice_ath10k_firmware-5.txt
 
 Licence: Redistributable. See LICENSE.QualcommAtheros_ath10k for details