component/patchelf: new component

extracted from nexedi/slapos!735
and updated to 0.11

component/patchelf/buildout.cfg

+[buildout]
+extends =
+  ../autoconf/buildout.cfg
+  ../automake/buildout.cfg
+  ../pkgconfig/buildout.cfg
+
+parts = 
+  patchelf
+
+[patchelf]
+recipe = slapos.recipe.cmmi
+shared = true
+url = https://github.com/NixOS/patchelf/archive/0.11.tar.gz
+md5sum = 6cffb77ee7a95bd314d954a6aeb53a02
+pre-configure = 
+  autoreconf -vif
+environment =
+  PATH=${pkgconfig:location}/bin:${autoconf:location}/bin:${automake:location}/bin:%(PATH)s