Fix FTBFS due to accidental double quote duplication

diff --git a/digikam/libs/dialogs/imagedialog.cpp b/digikam/libs/dialogs/imagedialog.cpp
index 879d7b0..4473024 100644
--- a/digikam/libs/dialogs/imagedialog.cpp
+++ b/digikam/libs/dialogs/imagedialog.cpp
@@ -230,7 +230,7 @@
 void ImageDialogPreview::slotFailedThumbnail(const KURL& /*url*/)
 {
     TDEIconLoader* iconLoader = TDEApplication::kApplication()->iconLoader();
-    d->imageLabel->setPixmap(iconLoader->loadIcon(""image-x-generic", TDEIcon::NoGroup, 128,
+    d->imageLabel->setPixmap(iconLoader->loadIcon("image-x-generic", TDEIcon::NoGroup, 128,
                              TDEIcon::DefaultState, 0, true));
 }
 
diff --git a/digikam/libs/thumbbar/thumbbar.cpp b/digikam/libs/thumbbar/thumbbar.cpp
index 63cdb64..53fa9b0 100644
--- a/digikam/libs/thumbbar/thumbbar.cpp
+++ b/digikam/libs/thumbbar/thumbbar.cpp
@@ -802,7 +802,7 @@
         return;
 
     TDEIconLoader* iconLoader = TDEApplication::kApplication()->iconLoader();
-    TQPixmap pix = iconLoader->loadIcon(""image-x-generic", TDEIcon::NoGroup, ThumbnailSize::Huge);
+    TQPixmap pix = iconLoader->loadIcon("image-x-generic", TDEIcon::NoGroup, ThumbnailSize::Huge);
 
     if (item->d->pixmap)
     {
diff --git a/digikam/utilities/cameragui/cameraiconview.cpp b/digikam/utilities/cameragui/cameraiconview.cpp
index a482839..e0f76a5 100644
--- a/digikam/utilities/cameragui/cameraiconview.cpp
+++ b/digikam/utilities/cameragui/cameraiconview.cpp
@@ -310,7 +310,7 @@
     else
     {
         TDEIconLoader *iconLoader = TDEApplication::kApplication()->iconLoader();
-        thumb = iconLoader->loadIcon(""application-x-zerosize", TDEIcon::Desktop,
+        thumb = iconLoader->loadIcon("application-x-zerosize", TDEIcon::Desktop,
                                      ThumbnailSize::Huge, TDEIcon::DefaultState, 0, true)
                                      .convertToImage();
     }