[bugfix] correct the type mappign keys

python/dune/perftool/target.py

@@ -4,8 +4,8 @@ import six
 from loopy.target import TargetBase
 from loopy.target.c.codegen.expression import LoopyCCodeMapper
 
-_registry = {numpy.float32: 'float',
-             numpy.int32 : 'int'}
+_registry = {'float32': 'float',
+             'int32' : 'int'}
 
 def dune_function_manglers():
     # OpenCL example impls: target/opencl/__init__.py:108