[gtk-doc] mkdb: fix undefined var

[Stefan Kost <stefkost src gnome org>]

commit 0d03479a4963ba731711cd5e324379472ea1c9f0
Author: Stefan Sauer <ensonic users sf net>
Date:   Wed Sep 14 15:50:32 2011 +0200

    mkdb: fix undefined var

 gtkdoc-mkdb.in |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/gtkdoc-mkdb.in b/gtkdoc-mkdb.in
index fe37697..add8b3a 100755
--- a/gtkdoc-mkdb.in
+++ b/gtkdoc-mkdb.in
@@ -1820,7 +1820,7 @@ sub OutputEnum {
     my $decl = $declaration;
 
     if ($decl =~ m/^\s*(typedef\s+)?enum\s*\w*\s*(?:\/\*.*\*\/)?\s*{(.*)}\s*\w*\s*;\s*$/s) {
-        my $has_typedef = ($1 ne "")? 1 : 0;
+        my $has_typedef = defined($1) ? 1 : 0;
         my $enum_contents = $2;
 
         foreach $decl_line (split (/\n/, $enum_contents)) {