Fix regression added in 1a3948cc that cause crashes.

theano/sandbox/cuda/nvcc_compiler.py

@@ -364,8 +364,6 @@ class NVCC_compiler(Compiler):
             console_encoding = getpreferredencoding()
             nvcc_stdout = decode_with(nvcc_stdout_raw, console_encoding)
             nvcc_stderr = decode_with(nvcc_stderr_raw, console_encoding)
-            p = subprocess.Popen(
-                cmd, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
         finally:
             os.chdir(orig_dir)