codec2: add C2SoftOpusEnc

Test: Tested with local AMediaCodec application to encode to opus
Bug: 115576456
Change-Id: I56f19f79fa2c9058651713594171ffed57bb9247
diff --git a/services/mediacodec/registrant/Android.bp b/services/mediacodec/registrant/Android.bp
index 8c40ad1..0d10044 100644
--- a/services/mediacodec/registrant/Android.bp
+++ b/services/mediacodec/registrant/Android.bp
@@ -38,6 +38,7 @@
         "libcodec2_soft_mp3dec",
         "libcodec2_soft_vorbisdec",
         "libcodec2_soft_opusdec",
+        "libcodec2_soft_opusenc",
         "libcodec2_soft_vp8dec",
         "libcodec2_soft_vp9dec",
         "libcodec2_soft_av1dec",