mdocml update breaks building tools on netbsd-5 host

["John D. Baker" <jdbaker%mylinuxisp.com@localhost>]

The recent update of mdocml logged beginning here:

  http://mail-index.NetBSD.org/source-changes/2014/01/05/msg050510.html

breaks building tools on netbsd-5/i386 host.

host:

NetBSD verthandi.technoskunk.fur 5.2_STABLE NetBSD 5.2_STABLE (VERTHANDI) #13: 
Wed Dec 18 05:44:53 CST 2013  
sysop%verthandi.technoskunk.fur@localhost:/d0/build/netbsd-5/obj/i386/sys/arch/i386/compile/VERTHANDI
 i386


failure example from macppc target:

[...]
#      link  mandoc/mandoc
cc -O -DOSNAME=\"NetBSD\ 6.99\" -DHAVE_CONFIG_H -I. 
-I/d0/build/current/tools/i386/include/compat -I/x/current/src/tools/compat 
-DHAVE_NBTOOL_CONFIG_H=1 -D_FILE_OFFSET_BITS=64   -o mandoc chars.lo main.lo out.lo 
tree.lo eqn_html.lo eqn_term.lo html.lo man_html.lo mdoc_html.lo tbl_html.lo man_term.lo 
mdoc_term.lo term.lo term_ascii.lo term_ps.lo tbl_term.lo man.lo man_hash.lo man_macro.lo 
man_validate.lo arch.lo att.lo lib.lo mdoc.lo mdoc_argv.lo mdoc_hash.lo mdoc_macro.lo 
mdoc_man.lo mdoc_validate.lo msec.lo st.lo vol.lo eqn.lo roff.lo tbl.lo tbl_data.lo 
tbl_layout.lo tbl_opts.lo mandoc.lo read.lo -L/d0/build/current/tools/i386/lib -lnbcompat 
-lrt -lz
mdoc_validate.lo: In function `post_hyph':
mdoc_validate.c:(.text+0x256a): undefined reference to `strnlen'
*** [mandoc] Error code 1
nbmake[3]: stopped in /x/current/src/tools/mandoc
1 error
nbmake[3]: stopped in /x/current/src/tools/mandoc
*** [dependall] Error code 2
nbmake[2]: stopped in /x/current/src/tools/mandoc
1 error
nbmake[2]: stopped in /x/current/src/tools/mandoc

*** Failed target:  dependall-mandoc
*** Failed command: _makedirtarget() { dir="$1"; shift; target="$1"; shift; case "${dir}" in /*) this="${dir}/"; real="${dir}" ;; .) this=""; 
real="/x/current/src/tools" ;; *) this="${dir}/"; real="/x/current/src/tools/${dir}" ;; esac; show=${this:-.}; echo "${target} ===> ${show%/}${1:+ (with: $@)}"; cd 
"${real}" && /d0/build/current/tools/i386/bin/nbmake _THISDIR_="${this}" "$@" ${target}; }; _makedirtarget mandoc dependall
*** Error code 2
Stop.
nbmake[1]: stopped in /x/current/src/tools
*** [build_install] Error code 1

nbmake: stopped in /x/current/src/tools
1 error

nbmake: stopped in /x/current/src/tools

ERROR: Failed to make build_install in "tools"
*** BUILD ABORTED ***

--
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