staging: speakup: remove redundant initialization of pointer p_key

staging: speakup: remove redundant initialization of pointer p_key

Pointer p_key is being initialized with a value that is never read,
it is assigned a new value later on. The initialization is redundant
and can be removed.

Reviewed-by: Samuel Thibault <samuel.thibault@ens-lyon.org>
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Addresses-Coverity: ("Unused value")
Link: https://lore.kernel.org/r/20200223153954.420731-1-colin.king@canonical.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>