cmd/cue: fix build
cmd/cue: fix build

Fixes Issue #34

Change-Id: Ib0474b79ed0aee706c6a981c9aaa431f4ca991ae
Reviewed-on: https://cue-review.googlesource.com/c/cue/+/1820
Reviewed-by: Marcel van Lohuizen <a22d082192f3ccf984644a4f482781f4c2d65180@google.com>

cuelang/cue