libgpiod

Currently, for the output of LineSettings.__repr__() to be eval()able,
the user must have pulled all the relevant definitions from gpiod.line
within the scope where it is used. Modify the output so that all the user
needs is `import gpiod`.

Reported-by: Vincent Fazio <vfazio@gmail.com>
Link: https://lore.kernel.org/r/20240920143203.6377-1-brgl@bgdev.pl


Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>