Revert float capability for downmixer

Revert floating point processing on downmixer.

This commits partially reverts d7d013446a64c6de9f0f2dfe098a721b140e0b48
Bug: 63760315

Test: Play multichannel movie
Change-Id: I16edf8767e02ef5d8ff63f52e8d1222ce0d09e22
diff --git a/media/libeffects/downmix/Android.mk b/media/libeffects/downmix/Android.mk
index 28b96d5..a5fbf14 100644
--- a/media/libeffects/downmix/Android.mk
+++ b/media/libeffects/downmix/Android.mk
@@ -20,7 +20,8 @@
 	$(call include-path-for, audio-effects) \
 	$(call include-path-for, audio-utils)
 
-LOCAL_CFLAGS += -fvisibility=hidden -DBUILD_FLOAT
+#-DBUILD_FLOAT
+LOCAL_CFLAGS += -fvisibility=hidden
 LOCAL_CFLAGS += -Wall -Werror
 
 LOCAL_HEADER_LIBRARIES += libhardware_headers