Rename icon to prevent install conflicts with the Qt6 frontend.

--- qt5/org.gnupg.pinentry-qt5.desktop.in.orig	2024-07-03 09:19:19 UTC
+++ qt5/org.gnupg.pinentry-qt5.desktop.in
@@ -4,6 +4,6 @@ NoDisplay=true
 Categories=Qt;Utility;
 Exec=@prefix@/bin/pinentry-qt5
 NoDisplay=true
-Icon=pinentry
+Icon=pinentry-qt5
 GenericName=Utility for entering GnuPG secrets
 X-KDE-Wayland-Interfaces=org_kde_kwin_keystate