ath10k: fix possible out of bound access of ath10k_rates array

While using 'ath10k_mac_get_rate_hw_value()' to obtain the hw value
from the passed bitrate, there is a chance of out of bound array access
when wrong bitrate is passed. This is fixed by comparing the bitrates
within the correct size of the ath10k_rates array.

Fixes commit f279294e ("ath10k: add support for configuring management
packet rate"). Also correction made to some indents used in the above commit.
Signed-off-by: Sriram R <srirrama@codeaurora.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>

drivers/net/wireless/ath/ath10k/mac.c

@@ -164,7 +164,7 @@ static int ath10k_mac_get_rate_hw_value(int bitrate)
 	if (ath10k_mac_bitrate_is_cck(bitrate))
 		hw_value_prefix = WMI_RATE_PREAMBLE_CCK << 6;
 
-	for (i = 0; i < sizeof(ath10k_rates); i++) {
+	for (i = 0; i < ARRAY_SIZE(ath10k_rates); i++) {
 		if (ath10k_rates[i].bitrate == bitrate)
 			return hw_value_prefix | ath10k_rates[i].hw_value;
 	}