eglgears_wayland, es2gears_wayland, egltri_wayland crash on wlroots-based compositors

wl_shell is deprecated and maybe removed.

See also https://github.com/KhronosGroup/Vulkan-Tools/pull/212

$ eglgears_wayland
EGL_VERSION = 1.4
Process 81754 stopped
* thread #1, name = 'eglgears_wayland', stop reason = signal SIGSEGV: invalid address (fault address: 0x0)
    frame #0: 0x00000008007e05d3 libwayland-client.so.0`wl_proxy_marshal_constructor(proxy=0x0000000000000000, opcode=0, interface=0x00000008007e9798) at wayland-client.c:830:41
   827          va_list ap;
   828
   829          va_start(ap, interface);
-> 830          wl_argument_from_va_list(proxy->object.interface->methods[opcode].signature,
   831                                   args, WL_CLOSURE_MAX_ARGS, ap);
   832          va_end(ap);
   833
(lldb) bt
* thread #1, name = 'eglgears_wayland', stop reason = signal SIGSEGV: invalid address (fault address: 0x0)
  * frame #0: 0x00000008007e05d3 libwayland-client.so.0`wl_proxy_marshal_constructor(proxy=0x0000000000000000, opcode=0, interface=0x00000008007e9798) at wayland-client.c:830:41
    frame #1: 0x0000000000206cbf eglgears_wayland`wl_shell_get_shell_surface(wl_shell=0x0000000000000000, surface=0x0000000801219720) at wayland-client-protocol.h:2926:7
    frame #2: 0x0000000000206b19 eglgears_wayland`_eglutNativeInitWindow(win=0x00000008012195e0, title="eglgears", x=0, y=0, w=300, h=300) at eglut_wayland.c:121:27
    frame #3: 0x0000000000206298 eglgears_wayland`_eglutCreateWindow(title="eglgears", x=0, y=0, w=300, h=300) at eglut.c:166:4
    frame #4: 0x0000000000206055 eglgears_wayland`eglutCreateWindow(title="eglgears") at eglut.c:312:10
    frame #5: 0x0000000000203859 eglgears_wayland`main(argc=1, argv=0x00007fffffffe0b0) at eglgears.c:289:4
    frame #6: 0x000000000020361f eglgears_wayland`_start(ap=<unavailable>, cleanup=<unavailable>) at crt1_c.c:75:7