FS-7514: add pkg-config checks for vlc

src/mod/formats/mod_vlc/Makefile.am

@@ -1,8 +1,18 @@
 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
+