staging: rtl8188eu: Remove unnecessary parantheses

Removed parantheses on the right hand side of assignments as they are
not needed.

This was done with Coccinelle:

@@ expression a, b; @@

a =
- (
b
- )
;

Signed-off-by: Bhaktipriya Shridhar <bhaktipriya96@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>