Fix common misspellings

Fixes generated by 'codespell' and manually reviewed.

Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
diff --git a/drivers/net/wireless/hostap/hostap_wlan.h b/drivers/net/wireless/hostap/hostap_wlan.h
index 1c66b3c..88dc6a5 100644
--- a/drivers/net/wireless/hostap/hostap_wlan.h
+++ b/drivers/net/wireless/hostap/hostap_wlan.h
@@ -853,7 +853,7 @@
 	struct work_struct comms_qual_update;
 
 	/* RSSI to dBm adjustment (for RX descriptor fields) */
-	int rssi_to_dBm; /* substract from RSSI to get approximate dBm value */
+	int rssi_to_dBm; /* subtract from RSSI to get approximate dBm value */
 
 	/* BSS list / protected by local->lock */
 	struct list_head bss_list;