gfxstream + rutabaga: meson support

- Add meson detection of rutabaga_gfx
- Build virtio-gpu-rutabaga.c + associated vga/pci files when
  present

Signed-off-by: Gurchetan Singh <gurchetansingh@chromium.org>
Tested-by: Alyssa Ross <hi@alyssa.is>
Tested-by: Emmanouil Pitsidianakis <manos.pitsidianakis@linaro.org>
Tested-by: Akihiko Odaki <akihiko.odaki@daynix.com>
Reviewed-by: Emmanouil Pitsidianakis <manos.pitsidianakis@linaro.org>
Reviewed-by: Antonio Caggiano <quic_acaggian@quicinc.com>
Reviewed-by: Akihiko Odaki <akihiko.odaki@daynix.com>
diff --git a/meson.build b/meson.build
index bd65a11..e0d1f84 100644
--- a/meson.build
+++ b/meson.build
@@ -1046,6 +1046,12 @@
                                        dependencies: virgl))
   endif
 endif
+rutabaga = not_found
+if not get_option('rutabaga_gfx').auto() or have_system or have_vhost_user_gpu
+  rutabaga = dependency('rutabaga_gfx_ffi',
+                         method: 'pkg-config',
+                         required: get_option('rutabaga_gfx'))
+endif
 blkio = not_found
 if not get_option('blkio').auto() or have_block
   blkio = dependency('blkio',
@@ -4277,6 +4283,7 @@
 summary_info += {'PAM':               pam}
 summary_info += {'iconv support':     iconv}
 summary_info += {'virgl support':     virgl}
+summary_info += {'rutabaga support':  rutabaga}
 summary_info += {'blkio support':     blkio}
 summary_info += {'curl support':      curl}
 summary_info += {'Multipath support': mpathpersist}