ath10k: add rx bitrate report for SDIO

For SDIO chip, its rx indication is struct htt_rx_indication_hl, which
does not include the bitrate info as well as PCIe, for PCIe, it use
function ath10k_htt_rx_h_rates to parse the bitrate info in struct
rx_ppdu_start and then report it to mac80211 via ieee80211_rx_status.

SDIO does not have the same info as PCIe, then iw command can not get
the rx bitrate by "iw wlan0 station dump".

for example, it always show 6.0 MBit/s
localhost ~ # iw wlan0 link
Connected to 3c:28:6d:96:fd:69 (on wlan0)
	SSID: kukui_test
	freq: 5180
	RX: 111800 bytes (595 packets)
	TX: 35419 bytes (202 packets)
	signal: -41 dBm
	rx bitrate: 6.0 MBit/s

This patch is to send WMI_TLV_REQUEST_PEER_STATS_INFO_CMDID to firmware
for ath10k_sta_statistics and save the rx bitrate for WMI event
WMI_TLV_PEER_STATS_INFO_EVENTID.

This patch only effect SDIO chip, ath10k_mac_sta_get_peer_stats_info
has check for bitrate_statistics of hw_params, this patch only enable
it for "qca6174 hw3.2 sdio".

Tested with QCA6174 SDIO firmware WLAN.RMH.4.4.1-00042.

Signed-off-by: Wen Gong <wgong@codeaurora.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20200427080416.8265-3-wgong@codeaurora.org