[Howto] FreeBSD 11 and postfix 3.2.0 (‘unknown system type’ error)

make error-message:

ATTENTION:
ATTENTION: Unknown system type: FreeBSD 11.0-RELEASE-p2
ATTENTION:
*** Error code 1

Solution:

insert into postfix-3.2.0/makedefs

 FreeBSD.11*) SYSTYPE=FREEBSD11
 : ${CC=cc}
 : ${SHLIB_SUFFIX=.so}
 : ${SHLIB_CFLAGS=-fPIC}
 : ${SHLIB_LD="${CC} -shared"' -Wl,-soname,${LIB}'}
 : ${SHLIB_RPATH='-Wl,-rpath,${SHLIB_DIR}'}
 : ${SHLIB_ENV="LD_LIBRARY_PATH=`pwd`/lib"}
 : ${PLUGIN_LD="${CC} -shared"}
 ;;

and into postfix-3.2.0/src/util/sys_devs.h

#if defined(FREEBSD2) || defined(FREEBSD3) || defined(FREEBSD4) \
 || defined(FREEBSD5) || defined(FREEBSD6) || defined(FREEBSD7) \
 || defined(FREEBSD8) || defined(FREEBSD9) || defined(FREEBSD10) \
 || defined(FREEBSD11)