cmd/dist: optional verbosity

This makes output less noisy. The build is fast enough not to require progress indication.

Signed-off-by: Ophestra <cat@gensokyo.uk>

all.sh

@@ -2,5 +2,9 @@
 
 TOOLCHAIN_VERSION="$(go version)"
 cd "$(dirname -- "$0")/"
-echo "# Building cmd/dist using ${TOOLCHAIN_VERSION}."
-go run -v --tags=dist ./cmd/dist
+echo "Building cmd/dist using ${TOOLCHAIN_VERSION}."
+FLAGS=''
+if test -n "$VERBOSE"; then
+    FLAGS="$FLAGS -v"
+fi
+go run $FLAGS --tags=dist ./cmd/dist