Fix flaky build: make version-probe pipes SIGPIPE-safe

util/build.sh runs with `set -eu -o pipefail`. `eval "$MAKE" --version | head -n2`
(and the analogous `as --version | head`) can race: head closes the pipe after N
lines, make/as catch SIGPIPE and exit non-zero, pipefail propagates the failure,
and errexit aborts the build before any compilation. Append `|| true` so these
purely-informational version prints can never fail the build.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

util/build.sh

@@ -121,8 +121,8 @@ then
 fi
 
 # Just show the useful info
-eval "$MAKE" --version | head -n2
-as --version | head -n1
+eval "$MAKE" --version | head -n2 || true
+as --version | head -n1 || true
 as --version | tail -n1
 ld -v
 autoconf --version