CVE-2022-50709 wifi: ath9k: avoid uninit memory read in ath9k_htc_rx_msg()

In the Linux kernel, the following vulnerability has been resolved: wifi: ath9k: avoid uninit memory read in ath9khtcrxmsg syzbot is reporting uninit value at ath9khtcrxmsg 1, for ioctlUSBRAWIOCTLEPWRITE can call ath9khifusbrxstream with pktlen = 0 but ath9khifusbrxstream uses devallocskbpktlen +...