staging: rtlwifi: Remove unnecessary conditions

Remove conditions with no effect. Issues found by Coccinelle's semantic
patch results for cond_no_effect.cocci. Eliminate checkpatch result, a
line should not end with a parenthesis.

Signed-off-by: Maya Nakamura <m.maya.nakamura@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>