libxml-simple-perl: Use BBCLASSEXTEND insteand of *-native recipe

It's not appropriate to require xxx.bb in xxx-native.bb, causing that
xxx-native depends on target recipe.

Use BBCLASSEXTEND to solve this issue.

(From OE-Core rev: aa8f6b64055c6576bcdb63d3bbf9ab47b87c0d59)

Signed-off-by: Dongxiao Xu <dongxiao.xu@intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

meta/recipes-devtools/perl/libxml-simple-perl-native_2.18.bb

@@ -1,7 +0,0 @@
-SECTION = "libs"
-
-inherit native
-
-require libxml-simple-perl_${PV}.bb
-
-DEPENDS += "libxml-parser-perl-native"

meta/recipes-devtools/perl/libxml-simple-perl_2.18.bb

@@ -14,3 +14,5 @@ S = "${WORKDIR}/XML-Simple-${PV}"
 EXTRA_PERLFLAGS = "-I ${STAGING_LIBDIR_NATIVE}/perl-native/perl/${@get_perl_version(d)}"
 
 inherit cpan
+
+BBCLASSEXTEND = "native"