afile: rename from aout_file for consistency with adummy and amem

modules/audio_output/Modules.am

-SOURCES_aout_file = file.c
 SOURCES_waveout = waveout.c windows_audio_common.h packet.c
 SOURCES_auhal = auhal.c packet.c
 SOURCES_audioqueue = audioqueue.c packet.c
@@ -8,14 +7,18 @@ libadummy_plugin_la_SOURCES = adummy.c
 libadummy_plugin_la_CFLAGS = $(AM_CFLAGS)
 libadummy_plugin_la_LIBADD = $(AM_LIBADD)
 
+libafile_plugin_la_SOURCES = file.c
+libafile_plugin_la_CFLAGS = $(AM_CFLAGS)
+libafile_plugin_la_LIBADD = $(AM_LIBADD)
+
 libamem_plugin_la_SOURCES = amem.c
 libamem_plugin_la_CFLAGS = $(AM_CFLAGS)
 libamem_plugin_la_LIBADD = $(AM_LIBADD)
 
 libvlc_LTLIBRARIES += \
 	libadummy_plugin.la \
-	libamem_plugin.la \
-	libaout_file_plugin.la
+	libafile_plugin.la \
+	libamem_plugin.la
 
 liboss_plugin_la_SOURCES = oss.c packet.c volume.h
 liboss_plugin_la_CFLAGS = $(AM_CFLAGS)