ui: deprecate legacy -show-cursor option

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>

qemu-deprecated.texi

@@ -148,6 +148,11 @@ QEMU 5.0 introduced an alternative syntax to specify the size of the translation
 block cache, @option{-accel tcg,tb-size=}.  The new syntax deprecates the
 previously available @option{-tb-size} option.
 
+@subsection -show-cursor option (since 5.0)
+
+Use @option{-display sdl,show-cursor=on} or
+ @option{-display gtk,show-cursor=on} instead.
+
 @section QEMU Machine Protocol (QMP) commands
 
 @subsection change (since 2.5.0)

vl.c

@@ -3562,6 +3562,8 @@ int main(int argc, char **argv, char **envp)
                 no_shutdown = 1;
                 break;
             case QEMU_OPTION_show_cursor:
+                warn_report("The -show-cursor option is deprecated, "
+                            "use -display {sdl,gtk},show-cursor=on instead");
                 dpy.has_show_cursor = true;
                 dpy.show_cursor = true;
                 break;