Staging: speakup: varhandlers: cleanup of function spk_get_punc_var

This patch does the following:
* changed the complicated if statements to simple case statements
* in case of E_DEFAULT, no need to return error as ERESTART,
because this is the user asked for. Hence function should return success.
* ret variable is 0 always, hence removed it.
* removed one ternary operator, as it was always returning the status value only,
and hence removed the status variable too

Signed-off-by: Saurabh Sengar <saurabh.truth@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>