ath11k: removing redundant reo unlock followed by immediate lock

Removed reo cmd lock and unlock which was acquiring the lock immediately
after unlock. Done for code clean up.

Signed-off-by: Sowmiya Sree Elavalagan <ssreeela@codeaurora.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/1591713432-26426-1-git-send-email-ssreeela@codeaurora.org