build: enable audio modules

Add audio/ to common-obj-m variable.

Also run both audio and ui variables through unnest-vars.
This avoids sdl.mo (exists in both audio/ and ui/) name clashes.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Message-id: 20180306074053.22856-4-kraxel@redhat.com

Makefile

@@ -425,6 +425,10 @@ dummy := $(call unnest-vars,, \
                 io-obj-y \
                 common-obj-y \
                 common-obj-m \
+                ui-obj-y \
+                ui-obj-m \
+                audio-obj-y \
+                audio-obj-m \
                 trace-obj-y)
 
 include $(SRC_PATH)/tests/Makefile.include

Makefile.objs

@@ -104,6 +104,7 @@ common-obj-$(CONFIG_LINUX) += fsdev/
 common-obj-y += migration/
 
 common-obj-y += audio/
+common-obj-m += audio/
 common-obj-y += hw/
 
 common-obj-y += replay/