ninja: Rename 'rule' -> 'rulename' in NinjaBuildElement
ninja: Rename 'rule' -> 'rulename' in NinjaBuildElement

Rename 'rule' to 'rulename' in the NinjaBuildElement class, we're going
to want a reference to the NinjaRule object as well.

jpakkane/meson,becm/meson,mesonbuild/meson,becm/meson,mesonbuild/meson,mesonbuild/meson,QuLogic/meson,QuLogic/meson,pexip/meson,pexip/meson,pexip/meson,mesonbuild/meson,jpakkane/meson,becm/meson,becm/meson,becm/meson,mesonbuild/meson,QuLogic/meson,jpakkane/meson,pexip/meson,pexip/meson,mesonbuild/meson,mesonbuild/meson,becm/meson,pexip/meson,QuLogic/meson,mesonbuild/meson,jpakkane/meson,becm/meson,QuLogic/meson,QuLogic/meson,pexip/meson,becm/meson,mesonbuild/meson,pexip/meson,jpakkane/meson,jpakkane/meson,QuLogic/meson,mesonbuild/meson,becm/meson,jpakkane/meson,jpakkane/meson,QuLogic/meson,pexip/meson,QuLogic/meson,pexip/meson,becm/meson,jpakkane/meson