Build broken with new gcc 4.8.3.

[henning petersen <henning.petersen%t-online.de@localhost>]

/usr/netbsd/tools.amd64/bin/x86_64--netbsd-gcc -O2
-I/usr/src/external/cddl/osnet/sys
-I/usr/src/external/cddl/osnet/include
-I/usr/src/external/cddl/osnet/dist  -I/usr/src/external/cddl/osnet/dist
 -I/usr/src/external/cddl/osnet/dist/head
-I/usr/src/external/cddl/osnet/dist/tools/ctf/common
-I/usr/src/external/cddl/osnet/dist/tools/ctf/cvt
-I/usr/src/external/cddl/osnet/dist/uts/common  -g  -std=gnu99 -Werror
  --sysroot=/usr/netbsd/dest.amd64  -c
/usr/src/external/cddl/osnet/dist/tools/ctf/cvt/alist.c
/usr/netbsd/tools.amd64/bin/nbctfconvert -g -L VERSION -g alist.o
ERROR: nbctfconvert: failed to initialize DWARF: Wrong CU version. Only
2 and 3 supported [dwarf_init_info(541)]
Removing alist.o

*** Failed target:  alist.o
*** Failed command: /usr/netbsd/tools.amd64/bin/nbctfconvert -g -L
VERSION -g alist.o
*** Error code 1

Stop.

I think that libdwarf/libelf is too old (no support for dwarf4).