samba4: add optional libbsd dependency

It's used for some small functions like md5 support, non-essential since
samba has an internal fallback for those, but still add it for
predictability.

Signed-off-by: Gustavo Zacarias <gustavo@zacarias.com.ar>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>

package/samba4/samba4.mk

@@ -11,6 +11,7 @@ SAMBA4_INSTALL_STAGING = YES
 SAMBA4_LICENSE = GPLv3+
 SAMBA4_LICENSE_FILES = COPYING
 SAMBA4_DEPENDENCIES = host-e2fsprogs host-heimdal e2fsprogs popt python zlib \
+	$(if $(BR2_PACKAGE_LIBBSD),libbsd) \
 	$(if $(BR2_PACKAGE_LIBCAP),libcap) \
 	$(if $(BR2_PACKAGE_READLINE),readline)