package/sdl2: drop video-x11-{xinerama, vm}

Support has been dropped since the major release 2.24.0:
https://github.com/libsdl-org/SDL/commit/7d7ec9c95146c44d4b4643ed552796bf07937057

Signed-off-by: Thomas Devoogdt <thomas@devoogdt.com>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>
(cherry picked from commit 1692f2514a48ee369e09753007e9c67ff90daaf3)
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

package/sdl2/sdl2.mk

@@ -112,13 +112,6 @@ else
 SDL2_CONF_OPTS += --disable-video-x11-xcursor
 endif
 
-ifeq ($(BR2_PACKAGE_XLIB_LIBXINERAMA),y)
-SDL2_DEPENDENCIES += xlib_libXinerama
-SDL2_CONF_OPTS += --enable-video-x11-xinerama
-else
-SDL2_CONF_OPTS += --disable-video-x11-xinerama
-endif
-
 ifeq ($(BR2_PACKAGE_XLIB_LIBXI),y)
 SDL2_DEPENDENCIES += xlib_libXi
 SDL2_CONF_OPTS += --enable-video-x11-xinput
@@ -140,13 +133,6 @@ else
 SDL2_CONF_OPTS += --disable-video-x11-scrnsaver
 endif
 
-ifeq ($(BR2_PACKAGE_XLIB_LIBXXF86VM),y)
-SDL2_DEPENDENCIES += xlib_libXxf86vm
-SDL2_CONF_OPTS += --enable-video-x11-vm
-else
-SDL2_CONF_OPTS += --disable-video-x11-vm
-endif
-
 else
 SDL2_CONF_OPTS += --disable-video-x11 --without-x
 endif