devel/blueprint-compiler: fix runtime on big-endian

Upstream commits https://gitlab.gnome.org/jwestman/blueprint-compiler/-/commit/0c0219551026ec9aec5487891e07d1ced3a31112 and https://gitlab.gnome.org/jwestman/blueprint-compiler/-/commit/057c767fbb595bb31d025c76547045273948aab1.