meson/vdpau: add missing soversion

This mirrors what autotools does in src/gallium/state_trackers/vdpau/Makefile.am
and src/gallium/targets/vdpau/Makefile.am:

  VDPAU_MAJOR = 1
  VDPAU_MINOR = 0
  libvdpau_gallium_la_LDFLAGS = -version-number $(VDPAU_MAJOR):$(VDPAU_MINOR)

Reported-by: Igor Gnatenko <i.gnatenko.brain@gmail.com>
Fixes: 68076b8747 "meson: build gallium vdpau state tracker"
Signed-off-by: Eric Engestrom <eric.engestrom@intel.com>
Reviewed-by: Emil Velikov <emil.velikov@collabora.com>
Reviewed-by: Dylan Baker <dylan@pnwbakers.com>

src/gallium/state_trackers/vdpau/meson.build

@@ -18,13 +18,20 @@
 # OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 # SOFTWARE.
 
+VDPAU_MAJOR = 1
+VDPAU_MINOR = 0
+
 libvdpau_st = static_library(
   'vdpau_st',
   files(
     'bitmap.c', 'decode.c', 'device.c', 'ftab.c', 'htab.c', 'mixer.c',
     'output.c', 'preemption.c', 'presentation.c', 'query.c', 'surface.c',
   ),
-  c_args : [c_vis_args, '-DVER_MAJOR=1', '-DVER_MINOR=0'],
+  c_args : [
+    c_vis_args,
+    '-DVER_MAJOR=@0@'.format(VDPAU_MAJOR),
+    '-DVER_MINOR=@0@'.format(VDPAU_MINOR),
+  ],
   include_directories : [
     inc_include, inc_src, inc_util, inc_gallium, inc_gallium_aux,
   ],

src/gallium/targets/vdpau/meson.build

@@ -54,13 +54,14 @@ libvdpau_gallium = shared_library(
     dep_thread, driver_r300, driver_r600, driver_radeonsi, driver_nouveau,
   ],
   link_depends : vdpau_link_depends,
+  soversion : '@0@.@1@.0'.format(VDPAU_MAJOR, VDPAU_MINOR),
 )
 foreach d : [[with_gallium_r300, 'r300'],
              [with_gallium_r600, 'r600'],
              [with_gallium_radeonsi, 'radeonsi'],
              [with_gallium_nouveau, 'nouveau']]
   if d[0]
-    vdpau_drivers += 'libvdpau_@0@.so.1.0.0'.format(d[1])
+    vdpau_drivers += 'libvdpau_@0@.so.@1@.@2@.0'.format(d[1], VDPAU_MAJOR, VDPAU_MINOR)
   endif
 endforeach