firmware: vpd: do not clear statically allocated data

ro_vpd and rw_vpd are static module-scope variables that are guaranteed
to be initialized with zeroes, there is no need for explicit memset().

Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Reviewed-by: Guenter Roeck <groeck@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>