Build libstagefright_soft_h264enc by default

related-to-bug: 6383440

Change-Id: I852941c72f9b7270ac6e5b094e4b2a0322643ac8
diff --git a/target/product/core.mk b/target/product/core.mk
index 75d42e3..7137f7f 100644
--- a/target/product/core.mk
+++ b/target/product/core.mk
@@ -99,6 +99,7 @@
     libstagefright_soft_amrwbenc \
     libstagefright_soft_g711dec \
     libstagefright_soft_h264dec \
+    libstagefright_soft_h264enc \
     libstagefright_soft_mp3dec \
     libstagefright_soft_mpeg4dec \
     libstagefright_soft_vorbisdec \