Use mptcp_lib_print_ok(), _warn(), and _err() helpers in script diag.sh
to print test results with colors.

Having colors helps to quickly identify issues when looking at a long
list of output logs and results.

Signed-off-by: Geliang Tang <geliang.tang@suse.com>
---
 tools/testing/selftests/net/mptcp/diag.sh | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/tools/testing/selftests/net/mptcp/diag.sh b/tools/testing/selftests/net/mptcp/diag.sh
index 3119811018fc..7cf1f602bf48 100755
--- a/tools/testing/selftests/net/mptcp/diag.sh
+++ b/tools/testing/selftests/net/mptcp/diag.sh
@@ -62,15 +62,15 @@ __chk_nr()
 	printf "%-50s" "$msg"
 	if [ $nr != $expected ]; then
 		if [ $nr = "$skip" ] && ! mptcp_lib_expect_all_features; then
-			echo "[ SKIP ] Feature probably not supported"
+			mptcp_lib_print_warn "[ SKIP ] Feature probably not supported"
 			mptcp_lib_result_skip "${msg}"
 		else
-			echo "[ FAIL ] expected $expected found $nr"
+			mptcp_lib_print_err "[ FAIL ] expected $expected found $nr"
 			mptcp_lib_result_fail "${msg}"
 			ret=$test_cnt
 		fi
 	else
-		echo "[  OK  ]"
+		mptcp_lib_print_ok "[  OK  ]"
 		mptcp_lib_result_pass "${msg}"
 	fi
 	test_cnt=$((test_cnt+1))
@@ -111,15 +111,15 @@ wait_msk_nr()
 
 	printf "%-50s" "$msg"
 	if [ $i -ge $timeout ]; then
-		echo "[ FAIL ] timeout while expecting $expected max $max last $nr"
+		mptcp_lib_print_err "[ FAIL ] timeout while expecting $expected max $max last $nr"
 		mptcp_lib_result_fail "${msg} # timeout"
 		ret=$test_cnt
 	elif [ $nr != $expected ]; then
-		echo "[ FAIL ] expected $expected found $nr"
+		mptcp_lib_print_err "[ FAIL ] expected $expected found $nr"
 		mptcp_lib_result_fail "${msg} # unexpected result"
 		ret=$test_cnt
 	else
-		echo "[  OK  ]"
+		mptcp_lib_print_ok "[  OK  ]"
 		mptcp_lib_result_pass "${msg}"
 	fi
 	test_cnt=$((test_cnt+1))
-- 
2.35.3