ath10k: fix missing a blank line after declarations

Fixes checkpatch warnings:

WARNING: Missing a blank line after declarations

Please note that some of the cases I fixed by moving the variable declarations
to the beginning of the function, which is the preferred style in ath10k.

Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>

diff --cc drivers/net/wireless/ath/ath10k/htt_rx.c
Simple merge

diff --cc drivers/net/wireless/ath/ath10k/mac.c
Simple merge

diff --cc drivers/net/wireless/ath/ath10k/wmi.c
Simple merge