ath11k: fix the value of msecs_to_jiffies in ath11k_debugfs_fw_stats_request

parameter of msecs_to_jiffies should be (3 * 1000) instead of (3 * HZ)

Tested-on: QCA6390 hw2.0 PCI WLAN.HST.1.0.1-01740-QCAHSTSWPLZ_V2_TO_X86-1

Signed-off-by: Wen Gong <quic_wgong@quicinc.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20211026032014.27010-1-quic_wgong@quicinc.com