bitbake.conf/debian.bbclass: Move AUTO_LIBNAME_PKGS definition to class file

Might as well move this default to the class which uses it allowing
for easier reading/understanding of the class.

(From OE-Core rev: 177aec177306e68bcd822dee6b29a7efbd558a91)

Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

meta/classes/debian.bbclass

@@ -9,6 +9,8 @@
 # Better expressed as ensure all RDEPENDS package before we package
 # This means we can't have circular RDEPENDS/RRECOMMENDS
 
+AUTO_LIBNAME_PKGS = "${PACKAGES}"
+
 inherit package
 
 DEBIANRDEP = "do_packagedata"