8.2.0rc0 Regression: '-display vnc' opens gtk display as well
Description of problem:
A VNC display is requested, but a GTK frontend is opened as well. A VNC client is able to connect.
Steps to reproduce:
1. /configure --enable-fdt=internal --target-list=x86_64-softmmu
2. make 
3. build/qemu-system-x86_64 -display vnc=:05 -k de
Additional information:
git bisect finally shows
```
484629fc8141eaa257f961b5e5e310a1bbd0f1a2 is the first bad commit
commit 484629fc8141eaa257f961b5e5e310a1bbd0f1a2
Author: Marc-André Lureau <marcandre.lureau@redhat.com>
Date:   Wed Oct 25 17:21:17 2023 +0400

    vl: simplify display_remote logic
    
    Bump the display_remote variable when the -vnc option is parsed, just
    like -spice.
    
    Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
    Reviewed-by: Thomas Huth <thuth@redhat.com>

 system/vl.c | 6 +-----
 1 file changed, 1 insertion(+), 5 deletions(-)
```