[glibmm/glibmm-2-56] tools/test_scripts/testheaders.sh: Fix a directory test

[Kjell Ahlstedt <kjellahl src gnome org>]

commit 6cd55492062df2232594a97d8c40680dfc8f7945
Author: Kjell Ahlstedt <kjellahlstedt gmail com>
Date:   Fri Oct 26 19:00:26 2018 +0200

    tools/test_scripts/testheaders.sh: Fix a directory test

 tools/test_scripts/testheaders.sh | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/tools/test_scripts/testheaders.sh b/tools/test_scripts/testheaders.sh
index 150ada4e..c66faa21 100755
--- a/tools/test_scripts/testheaders.sh
+++ b/tools/test_scripts/testheaders.sh
@@ -53,7 +53,7 @@ shift
 # Search for more directories to include in CFLAGS.
 for i in "$@"
 do
-  if [ -d "$1" ]
+  if [ -d "$i" ]
   then
     idirs+=" -I$i"
   fi