staging: speakup: remove multiple assignments

Remove multiple assignments by factorizing.

Coccinelle semantic patch used:
@@ identifier x,y; constant z; @@
- x=y=z;
+ x=z;
+ y=z;

Signed-off-by: Alison Schofield <amsfield22@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>