Use shared lib of libselinux in runconuid instead of static one.

libselinux is being used as shared lib by many other modules.
So using its shared lib will reduce total image size.

Size diff on angler build image is as follows.

runconuid: 19912 -> 11256 (-8656)

Test: building succeeded, and the image was tested on angler.
Bug: 33056637
Change-Id: I6272486fdacef06c30d25f1718651757d873eb1b

runconuid/Android.mk

@@ -10,6 +10,6 @@ LOCAL_MODULE:= runconuid
 LOCAL_MODULE_PATH := $(TARGET_OUT_OPTIONAL_EXECUTABLES)
 LOCAL_MODULE_TAGS := debug
 
-LOCAL_STATIC_LIBRARIES := libselinux
+LOCAL_SHARED_LIBRARIES := libselinux
 
 include $(BUILD_EXECUTABLE)