[gnome-commander/ConfigurableFileListColumns] Remove unused struct member, initialize others with nullptr

[Uwe Scholz <uwescholz src gnome org>]

commit c9e8ccbe27f2efb539527b8a23f99940467010c9
Author: Uwe Scholz <u scholz83 gmx de>
Date:   Sat May 4 21:28:19 2019 +0200

    Remove unused struct member, initialize others with nullptr

 src/gnome-cmd-file-list.cc | 8 +++-----
 1 file changed, 3 insertions(+), 5 deletions(-)
---
diff --git a/src/gnome-cmd-file-list.cc b/src/gnome-cmd-file-list.cc
index 11f990bf..c51339fc 100644
--- a/src/gnome-cmd-file-list.cc
+++ b/src/gnome-cmd-file-list.cc
@@ -293,11 +293,10 @@ inline gchar *strip_extension (const gchar *fname)
 
 struct FileFormatData
 {
-    gchar *text[GnomeCmdFileList::NUM_COLUMNS];
+    gchar *text[GnomeCmdFileList::NUM_COLUMNS] {nullptr};
 
-    gchar *dpath;
-    gchar *fname;
-    gchar *fext;
+    gchar *dpath {nullptr};
+    gchar *fname {nullptr};
 
     static gchar empty_string[];
 
@@ -400,7 +399,6 @@ FileFormatData::~FileFormatData()
 {
     g_free (dpath);
     g_free (fname);
-    g_free (fext);
 }