compiler: fix brace formatting

Just happened to notice this one.

Change-Id: I53c3183e28eaec30eb702f0101b8ac208b23895f
Reviewed-on: https://go-review.googlesource.com/c/gofrontend/+/197698
Reviewed-by: Than McIntosh <thanm@google.com>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
1 file changed