winrt: Delete old rtf license file if present
diff --git a/winrt/InstallerRT.nsi b/winrt/InstallerRT.nsi
index a37d93a..7244837 100644
--- a/winrt/InstallerRT.nsi
+++ b/winrt/InstallerRT.nsi
@@ -126,6 +126,7 @@
 # Installer
 Section
     Delete "$INSTDIR\install.log"
+    Delete "$INSTDIR\VULKANRT_LICENSE.rtf"
     LogSet on
 
     # Disable filesystem redirection