configure.ac: check require_basic_egl only if egl enabled

Otherwise the configuration fails when building independant libs
like vdpau, vaapi or omx

Fixes: 1ac40173c2a ("configure.ac: simplify EGL requirements for
drivers dependent on EGL")

Signed-off-by: Leo Liu <leo.liu@amd.com>
Reviewed-by: Emil Velikov <emil.velikov@collabora.com>
Cc: "17.0" <mesa-stable@lists.freedesktop.org>
1 file changed