staging: pi433: remove unnecessary parentheses pointed out by checkpatch.pl

Checkpatch reports 'Unnecessary parentheses around <lines>'.
Fix this by removing extraneous parentheses where applicable.

Signed-off-by: Paulo Miguel Almeida <paulo.miguel.almeida.rodenas@gmail.com>
Link: https://lore.kernel.org/r/20211222070256.GA7644@localhost.localdomain


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