util/lint/lint: Show lint script output as it's running

The checkpatch script takes a really long time to run, and when the
output is buffered to wait until it's finished, it's hard to tell if
the script is actually doing anything.

Instead, use tee to log the output and display it at the same time.

Change-Id: I3cf36e5e6ca28584103888ee1c6f125320ac068a
Signed-off-by: Martin Roth <martinroth@google.com>
Reviewed-on: https://review.coreboot.org/17125
Reviewed-by: Patrick Georgi <pgeorgi@google.com>
Tested-by: build bot (Jenkins)

util/lint/lint

@@ -50,15 +50,14 @@ for script in "$(dirname "$0")/${1}-"*; do
 	grep "^# DESCR:" "$script" | sed "s,.*DESCR: *,,"
 	echo "========"
 	junit_write "	<testcase classname='lint' name='$(basename "$script")'>"
-	$script > "$LINTLOG"
+	$script | tee "$LINTLOG"
 
 	#if the lint script gives any output, that's a failure
 	if [ "$(wc -l < "$LINTLOG")" -eq 0 ]; then
 		echo "success"
 		junit_write "		<system-out><![CDATA[success]]></system-out>"
 	else
-		echo "test failed:"
-		cat "$LINTLOG"
+		echo "test failed"
 		junit_write "		<failure type='testFailed'><![CDATA["
 		junit_write "$(cat "$LINTLOG")"
 		junit_write "]]></failure>"