[build] Fix interaction between shave, gtk-doc and libtool 1.x
[build] Fix interaction between shave, gtk-doc and libtool 1.x

gtk-doc.make does not specify --tag=CC when invoking libtool, letting
it decide which tag to use.  Something that fails with libtool 1.x and
when having CC set to funny things.

tardyp/clutter,djdeath/clutter-multithreaded,spatulasnout/clutter,ebassi/clutter,spatulasnout/clutter,heysion/clutter-clone,tardyp/clutter,GNOME/clutter,Distrotech/clutter,djdeath/clutter-android,GNOME/clutter,jigpu/clutter,Distrotech/clutter,ebassi/clutter,heysion/clutter-clone,nobled/clutter,ebassi/clutter,Distrotech/clutter,djdeath/clutter,nobled/clutter,jigpu/clutter,rkudiyarov/clutter_osx,Distrotech/clutter,spatulasnout/clutter,djdeath/clutter,collects/clutter,djdeath/clutter,GNOME/clutter,spatulasnout/clutter,nobled/clutter,jigpu/clutter,djdeath/clutter-android,jigpu/clutter,djdeath/clutter-multithreaded,jigpu/clutter,GNOME/clutter,dlespiau/clutter,collects/clutter,kerrickstaley/clutter-vala,rkudiyarov/clutter_osx,ebassi/clutter,rkudiyarov/clutter_osx,kerrickstaley/clutter-vala,kerrickstaley/clutter-vala,ebassi/clutter,djdeath/clutter,djdeath/clutter-multithreaded,djdeath/clutter-android,djdeath/clutter-android,heysion/clutter-clone,collects/clutter,rkudiyarov/clutter_osx,djdeath/clutter-multithreaded,Distrotech/clutter,kerrickstaley/clutter-vala,GNOME/clutter,Distrotech/clutter,djdeath/clutter,dlespiau/clutter,dlespiau/clutter,tardyp/clutter,collects/clutter,spatulasnout/clutter,heysion/clutter-clone,djdeath/clutter,collects/clutter,jigpu/clutter,djdeath/clutter-android,heysion/clutter-clone