omni: move audio files to product and migrate to OMNI_PRODUCT_PROPERTIES

also remove all dalkik config files

Based on https://android.googlesource.com/platform/frameworks/base/+/eaec50becfc8bb606f6d117e996bed56351c2549%5E%21/#F0

Change-Id: I77ab64833abc7d0ff8b35e4a7abb7621713f6de9
diff --git a/config/version.mk b/config/version.mk
index f7aeda5..c5583fa 100644
--- a/config/version.mk
+++ b/config/version.mk
@@ -19,6 +19,6 @@
 endif
 
 # Apply it to build.prop
-PRODUCT_SYSTEM_DEFAULT_PROPERTIES += \
+OMNI_PRODUCT_PROPERTIES += \
     ro.modversion=OmniROM-$(ROM_VERSION) \
     ro.omni.version=$(ROM_VERSION)