staging: rtl8723bs: remove unnecessary parentheses in if condition

fix following post-commit hook checkpatch issue:

CHECK: Unnecessary parentheses around pcmdpriv->cmd_queue.queue
85: FILE: drivers/staging/rtl8723bs/core/rtw_cmd.c:422:
+		if (list_empty(&(pcmdpriv->cmd_queue.queue)))

Signed-off-by: Fabio Aiuto <fabioaiuto83@gmail.com>
Link: https://lore.kernel.org/r/3f5cf6b7b9aa5a0fa09b71278fdc361e9f113c41.1617802415.git.fabioaiuto83@gmail.com


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>