Revert "Fix docs"

This reverts commit 303a17b.

Author: sethrj

doc/usage/input/problem.rst

@@ -53,16 +53,16 @@ structures:
 The primary generator, similar to Geant4's "particle gun", has different
 configuration options:
 
-.. doxygentypedef:: celeritas::inp::AngleDistribution
-.. doxygentypedef:: celeritas::inp::EnergyDistribution
 .. doxygentypedef:: celeritas::inp::Events
-.. doxygentypedef:: celeritas::inp::MonodirectionalDistribution
-.. doxygentypedef:: celeritas::inp::MonoenergeticDistribution
-.. doxygentypedef:: celeritas::inp::PointDistribution
 .. doxygentypedef:: celeritas::inp::ShapeDistribution
+.. doxygentypedef:: celeritas::inp::AngleDistribution
+.. doxygentypedef:: celeritas::inp::EnergyDistribution
 
+.. celerstruct:: inp::PointDistribution
 .. celerstruct:: inp::UniformBoxDistribution
 .. celerstruct:: inp::IsotropicDistribution
+.. celerstruct:: inp::MonodirectionalDistribution
+.. celerstruct:: inp::MonoenergeticDistribution
 
 
 .. _inp_system: