meson.build: change operator combining bools from + to and

upstream meson stopped allowing combining boolean with the plus
operator, and now requires using the logical and operator

reference:
https://github.com/mesonbuild/meson/commit/43302d3296baff6aeaf8e03f5d701b0402e37a6c

Fixes: https://github.com/systemd/systemd/issues/20632

Backport fix from,
https://github.com/systemd/systemd/commit/c29537f39e4f413a6cbfe9669fa121bdd6d8b36f



Signed-off-by: Vignesh Raman <vignesh.raman@collabora.com>