remove unused type variable

Cython/Compiler/ExprNodes.py

@@ -25,7 +25,7 @@ import Nodes
 from Nodes import Node
 import PyrexTypes
 from PyrexTypes import py_object_type, c_long_type, typecast, error_type, \
-     unspecified_type, cython_memoryview_ptr_type
+    unspecified_type
 import TypeSlots
 from Builtin import list_type, tuple_type, set_type, dict_type, \
      unicode_type, str_type, bytes_type, type_type

Cython/Compiler/PyrexTypes.py

@@ -3513,8 +3513,6 @@ c_pyx_buffer_nd_type = CStructOrUnionType("__Pyx_LocalBuf_ND", "struct",
 cython_memoryview_type = CStructOrUnionType("__pyx_memoryview_obj", "struct",
                                       None, 0, "__pyx_memoryview_obj")
 
-cython_memoryview_ptr_type = CPtrType(cython_memoryview_type)
-
 memoryviewslice_type = CStructOrUnionType("memoryviewslice", "struct",
                                           None, 1, "__Pyx_memviewslice")