On 32-bit architectures the size of a gulong will typically be 4 bytes
while we try to package an 8-byte integer when creating the edge event
variant. The client also expects wrong types and crashes. Use strict
type sizes for sending the events.
Closes: https://github.com/brgl/libgpiod/issues/103
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>