Fix typo.

Author: JulianGro

cmake/templates/NSIS.template.in

@@ -1564,7 +1564,7 @@ Section "Uninstall"
     StrCmp "$MUI_TEMP" "$SMPROGRAMS" startMenuDeleteLoopDone startMenuDeleteLoop
   startMenuDeleteLoopDone:
 
-  ; If the user changed the shortcut, then untinstall may not work. This should
+  ; If the user changed the shortcut, then uninstall may not work. This should
   ; try to fix it.
   StrCpy $MUI_TEMP "$START_MENU"
   Delete "$SMPROGRAMS\$MUI_TEMP\Uninstall.lnk"