staging: speakup: Add a pair of braces

Add a pair of braces to make all arms of the if statement consistent.
Issue found by checkpatch.pl.

Signed-off-by: Maya Nakamura <m.maya.nakamura@gmail.com>
Acked-by: Samuel Thibault <samuel.thibault@ens-lyon.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>