FS-7514: add pkg-config checks for vlc

configure.ac

@@ -1246,6 +1246,10 @@ PKG_CHECK_MODULES([AVFORMAT], [libavformat >= 53.21.1],[
   AM_CONDITIONAL([HAVE_AVFORMAT],[true])],[
   AC_MSG_RESULT([no]); AM_CONDITIONAL([HAVE_AVFORMAT],[false])])
 
+PKG_CHECK_MODULES([VLC], [libvlc >= 2.1.0],[
+  AM_CONDITIONAL([HAVE_VLC],[true])],[
+  AC_MSG_RESULT([no]); AM_CONDITIONAL([HAVE_VLC],[false])])
+
 PKG_CHECK_MODULES([MEMCACHED], [libmemcached >= 0.31],[
   AM_CONDITIONAL([HAVE_MEMCACHED],[true])
   MEMCACHED_LIBS="${MEMCACHED_LIBS} -lpthread"

src/mod/formats/mod_vlc/Makefile.am

 include $(top_srcdir)/build/modmake.rulesam
 MODNAME=mod_vlc
 
+if HAVE_VLC
+
 mod_LTLIBRARIES = mod_vlc.la
 mod_vlc_la_SOURCES  = mod_vlc.c
-mod_vlc_la_CFLAGS   = $(AM_CFLAGS)
-mod_vlc_la_LIBADD   = $(switch_builddir)/libfreeswitch.la 
-mod_vlc_la_LDFLAGS  = -avoid-version -module -no-undefined -shared -lvlc
+mod_vlc_la_CFLAGS   = $(AM_CFLAGS) $(VLC_CFLAGS)
+mod_vlc_la_LIBADD   = $(switch_builddir)/libfreeswitch.la $(VLC_LIBS)
+mod_vlc_la_LDFLAGS  = -avoid-version -module -no-undefined -shared
+
+else
+install: error
+all: error
+error:
+	$(error You must install libvlc-dev to build mod_vlc)
+endif
+