[BUG] gallium-gbm-target requires drm-pipe-loader

[David Herrmann]

Hi

The recently added gbm gallium target
(./src/gallium/targets/gbm/gbm.c) requires HAVE_DRM_PIPE_LOADER for
pipe_loader_drm_probe(). Otherwise, the compiler fails with an
unresolved function-name.

However, HAVE_DRM_PIPE_LOADER is not defined when compiling i915 only,
so I need to compile gallium-nouveau, too, to get this symbol (or some
other driver that pulls in HAVE_DRM_PIPE_LOADER). It's
gallium_require_drm_loader() in configure.ac which defines this symbol
and I actually have no idea how to fix this bug but include this in
the "xi915)" case directly below the function definition.

Maybe you know a better fix.

Reproducable with current git and:
./autogen.sh --prefix=/usr --with-dri-driverdir=/usr/lib/xorg/modules/dri \
		--with-dri-drivers=i915 \
		--with-gallium-drivers=svga,swrast \
		--with-egl-platforms=drm,x11,wayland \
		--enable-gallium-llvm \
		--enable-gallium-egl \
		--enable-shared-dricore \
		--enable-shared-glapi \
		--enable-egl \
		--enable-gles1 \
		--enable-gles2 \
		--enable-openvg \
		--enable-glx-tls \
		--enable-xcb \
		--enable-texture-float

Thanks
David