package/nvidia-driver: depends on xlib_libX11 & xlib_libXext

package/nvidia-driver: depends on xlib_libX11 & xlib_libXext

Fix libglu build error

  CXXLD    libGLU.la
/home/buildroot/br4/output/host/lib/gcc/i586-buildroot-linux-gnu/6.4.0/../../../../i586-buildroot-linux-gnu/bin/ld: cannot find -lXext
/home/buildroot/br4/output/host/lib/gcc/i586-buildroot-linux-gnu/6.4.0/../../../../i586-buildroot-linux-gnu/bin/ld: cannot find -lX11
collect2: error: ld returned 1 exit status

using this defconfig

BR2_TOOLCHAIN_BUILDROOT_GLIBC=y
BR2_TOOLCHAIN_BUILDROOT_CXX=y
BR2_PACKAGE_XORG7=y
BR2_PACKAGE_XSERVER_XORG_SERVER=y
BR2_PACKAGE_NVIDIA_DRIVER=y
BR2_PACKAGE_LIBGLU=y

The nvidia binary blob is linked to libX11.so & libEext.so

$ output/host/bin/i586-buildroot-linux-gnu-readelf -a output/target/usr/lib/libGL.so | grep NEEDED
 0x00000001 (NEEDED)                     Shared library: [libnvidia-tls.so.381.09]
 0x00000001 (NEEDED)                     Shared library: [libnvidia-glcore.so.381.09]
 0x00000001 (NEEDED)                     Shared library: [libX11.so.6]
 0x00000001 (NEEDED)                     Shared library: [libXext.so.6]
 0x00000001 (NEEDED)                     Shared library: [libc.so.6]
 0x00000001 (NEEDED)                     Shared library: [libdl.so.2]

which is also reflected by Libs-section of package/nvidia-driver/gl.pc.

To allow other packages linking to libGL.so provided by this package we
need to reflect the fact that xlib_libX11 & xlib_libXext are not
runtime-only dependencies.

Signed-off-by: Bernd Kuhls <bernd.kuhls@t-online.de>
Signed-off-by: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be>