anv/gen7: Add memory barrier to vkCmdWaitEvents call

We also have this barrier call for gen8 vkCmdWaitEvents.

We don't implement waiting on events for gen7 yet, but this barrier at
least helps to not regress CTS cases when data caching is enabled.
Without this, the tests would intermittently report a failure when the
data cache was enabled.

Signed-off-by: Jordan Justen <jordan.l.justen@intel.com>
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>

src/intel/vulkan/gen7_cmd_buffer.c

@@ -546,4 +546,10 @@ void genX(CmdWaitEvents)(
     const VkImageMemoryBarrier*                 pImageMemoryBarriers)
 {
    stub();
+
+   genX(CmdPipelineBarrier)(commandBuffer, srcStageMask, destStageMask,
+                            false, /* byRegion */
+                            memoryBarrierCount, pMemoryBarriers,
+                            bufferMemoryBarrierCount, pBufferMemoryBarriers,
+                            imageMemoryBarrierCount, pImageMemoryBarriers);
 }