ibrcommon: add missing dependency on host-pkgconf

pkg-config is used by ibrcommon to detect the availability of openssl,
libnl and libxml2, so we must depend on host-pkgconf.

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>

package/ibrcommon/ibrcommon.mk

@@ -10,6 +10,7 @@ IBRCOMMON_SITE = https://www.ibr.cs.tu-bs.de/projects/ibr-dtn/releases/
 IBRCOMMON_INSTALL_STAGING = YES
 IBRCOMMON_LICENSE = Apache-2.0
 IBRCOMMON_LICENSE_FILES = COPYING README
+IBRCOMMON_DEPENDENCIES = host-pkgconf
 
 ifeq ($(BR2_PACKAGE_OPENSSL),y)
 IBRCOMMON_DEPENDENCIES += openssl