virtio: video: change minimum input buffer of decoder to 1

The decoder should be able to start decoding when receiving 1 input
buffer. This CL changes the minimum input buffer from 2 to 1.

BUG=b:176266656
TEST=android.media.cts.DecoderTest#testEOSBehaviorVP8

Change-Id: I2b055b145993d35c00a07bc7081db84117e36423
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/crosvm/+/2602297
Tested-by: Chih-Yu Huang <akahuang@chromium.org>
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Keiichi Watanabe <keiichiw@chromium.org>
Commit-Queue: Chih-Yu Huang <akahuang@chromium.org>
diff --git a/devices/src/virtio/video/decoder/mod.rs b/devices/src/virtio/video/decoder/mod.rs
index d9ac78f..4300a8d 100644
--- a/devices/src/virtio/video/decoder/mod.rs
+++ b/devices/src/virtio/video/decoder/mod.rs
@@ -182,7 +182,7 @@
             stream_id,
             in_params: Params {
                 format: Some(format),
-                min_buffers: 2,
+                min_buffers: 1,
                 max_buffers: 32,
                 plane_formats: vec![Default::default()],
                 ..Default::default()