plugin support for "other" system (non Linux UNIX)

Signed-off-by: Jean-Baptiste Kempf <jb@videolan.org>
(cherry picked from commit 8d12038f945bb965b50eece8ceca77c856b15694)
Signed-off-by: Rafaël Carré <funman@videolan.org>

src/Makefile.am

@@ -293,6 +293,7 @@ SOURCES_libvlc_other = \
 	posix/filesystem.c \
 	network/poll.c \
 	posix/thread.c \
+	posix/plugin.c \
 	posix/specific.c \
 	$(NULL)