mesa-gallium-vdpau: Re-add missing vdpau LIB_DEPENDS

Reported by:	vishwin
Sponsored by:	Beckhoff Automation GmbH & Co. KG

graphics/mesa-gallium-vdpau/Makefile

@@ -11,7 +11,8 @@ LICENSE_FILE=	${WRKSRC}/docs/license.rst
 ONLY_FOR_ARCHS=		aarch64 amd64 i386 powerpc64 powerpc64le
 ONLY_FOR_ARCHS_REASON=	used only by AMD/Radeon hardware
 
-LIB_DEPENDS=	libzstd.so:archivers/zstd
+LIB_DEPENDS=	libvdpau.so:multimedia/libvdpau \
+		libzstd.so:archivers/zstd
 
 USES=		llvm:lib,noexport