bindings: cxx: set the ABI version to 1.0.0
bindings: cxx: set the ABI version to 1.0.0

The C++ bindings ABI that will be released in v1.1 is considered
stable. Set it to 1.0.0 for the release.

Signed-off-by: Bartosz Golaszewski <108de5fbc428215dc26df4468b48691526611148@gmail.com>

brgl/libgpiod,brgl/libgpiod,brgl/libgpiod,brgl/libgpiod