psppire-output-view: Use correct enumeration type in call.
[pspp] / src /
drwxr-xr-x   ..
-rw-r--r-- 1660 automake.mk
drwxr-xr-x - data
drwxr-xr-x - language
drwxr-xr-x - libpspp
drwxr-xr-x - math
drwxr-xr-x - output
drwxr-xr-x - ui