dhcp: search libxml2 for bind

libdns requires libxml2 if bind was built with libxml2 support
enabled. Compilation will fail for omapip/test.c in case
-lxml2 isn't used during the build. So, we add losely coupled
search path which will pick up the lib if it is present.

(From OE-Core rev: a9e4edb2b5304e7493b791f3b3f76d37af5433ff)

Signed-off-by: Awais Belal <awais_belal@mentor.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

meta/recipes-connectivity/dhcp/dhcp.inc

@@ -18,7 +18,8 @@ SRC_URI = "ftp://ftp.isc.org/isc/dhcp/${PV}/dhcp-${PV}.tar.gz \
            file://init-server file://default-server \
            file://dhclient.conf file://dhcpd.conf \
            file://dhcpd.service file://dhcrelay.service \
-           file://dhcpd6.service "
+           file://dhcpd6.service \
+           file://search-for-libxml2.patch "
 
 UPSTREAM_CHECK_URI = "ftp://ftp.isc.org/isc/dhcp/"
 UPSTREAM_CHECK_REGEX = "(?P<pver>\d+\.\d+\.(\d+?))/"

meta/recipes-connectivity/dhcp/dhcp/search-for-libxml2.patch

@@ -0,0 +1,23 @@
+libdns requires libxml2 if bind was built with libxml2 support
+enabled. Compilation will fail for omapip/test.c in case
+lxml2 isn't used during the build. So, we add losely coupled
+search path which will pick up the lib if it is present.
+
+Signed-off-by: Awais Belal <awais_belal@mentor.com>
+Upstream-Status: Pending
+
+diff --git a/configure.ac b/configure.ac
+index c9dc8b5..85f59be 100644
+--- a/configure.ac
++++ b/configure.ac
+@@ -602,6 +602,10 @@ no)
+ esac
+ AC_SUBST([libbind])
+ 
++# We need to find libxml2 if bind was built with support enabled
++# otherwise we'll fail to build omapip/test.c
++AC_SEARCH_LIBS(xmlTextWriterStartElement, [xml2],)
++
+ # OpenLDAP support.
+ AC_ARG_WITH(ldap,
+     AS_HELP_STRING([--with-ldap],[enable OpenLDAP support in dhcpd (default is no)]),