graphviz: added PACKAGECONFIG for librsvg

nativesdk-librsvg is not available anymore ([2], transition to Rust).
According to [2], graphviz can be used fine (even with svg images)
without librsvg.

[1] oe-core: 67dd505c42 ("librsvg: do not enable nativesdk")
[2] https://www.linuxfromscratch.org/blfs/view/cvs/general/graphviz.html

Signed-off-by: Christian Eggers <ceggers@arri.de>
Signed-off-by: Khem Raj <raj.khem@gmail.com>

meta-oe/recipes-graphics/graphviz/graphviz_2.44.1.bb

@@ -9,7 +9,6 @@ DEPENDS = " \
     groff-native \
     libtool \
     gdk-pixbuf \
-    librsvg \
     cairo \
     pango \
     expat \
@@ -34,6 +33,10 @@ SRC_URI:append:class-nativesdk = "\
 "
 SRC_URI[sha256sum] = "8e1b34763254935243ccdb83c6ce108f531876d7a5dfd443f255e6418b8ea313"
 
+PACKAGECONFIG ??= "librsvg"
+PACKAGECONFIG:class-nativesdk ??= ""
+PACKAGECONFIG[librsvg] = "--with-librsvg,--without-librsvg,librsvg"
+
 EXTRA_OECONF:append = " PS2PDF=/bin/echo"
 
 EXTRA_OECONF:class-target = "\