security/heimdal: Fix build

Fix build due to many undefined symbols listed in version.map. The
problem is that the listed functions are conditionally built and since
they exist in FreeBSD they are not built but they are still referenced
in version.map.

PR:		275979
MFH:		2024Q1
Approved by:	portmgr (just fix it)

security/heimdal/Makefile

@@ -45,6 +45,7 @@ CONFIGURE_ARGS=	--with-berkeley-db \
 		--sysconfdir="${PREFIX}/etc"
 # XXX --with-readline picks up libreadline even if found in /usr/lib.
 MAKE_ENV=	INSTALL_CATPAGES=no
+LDFLAGS=	-Wl,--undefined-version
 INSTALL_TARGET=	install-strip
 .if !exists(/etc/rc.d/ipropd_master)
 USE_RC_SUBR=	ipropd_master ipropd_slave