tools, with latest regexp updates

[bch <brad.harder%gmail.com@localhost>]

With latest (Mon Feb 29 17:18:06 PST 2016) code, building tools to
reflect latest regexp work to libnbcompat:


#   compile  compat/regsub.lo
cc -O  -I. -I./include -I/usr/src/tools/compat
-I/usr/src/tools/compat/sys  -DHAVE_NBTOOL_CONFIG_H=1
-D_FILE_OFFSET_BITS=64 -D__DBINTERFACE_PRIVATE -c -o regsub.lo.o
/usr/src/tools/compat/../../lib/libc/regex/regsub.c
In file included from ./nbtool_config.h:720:0,
                 from /usr/src/tools/compat/regex.h:3,
                 from /usr/src/tools/compat/../../lib/libc/regex/regsub.c:40:
/usr/src/tools/compat/compat_defs.h:72:2: error: #error _NETBSD_SOURCE
is *not* to be defined.
 #error _NETBSD_SOURCE is *not* to be defined.
  ^
In file included from ./nbtool_config.h:720:0,
                 from /usr/src/tools/compat/regex.h:3,
                 from /usr/src/tools/compat/../../lib/libc/regex/regsub.c:40:
/usr/src/tools/compat/compat_defs.h:257:8: error: redefinition of
'struct _dirdesc'
 struct _dirdesc {
        ^
In file included from /usr/src/tools/compat/compat_defs.h:169:0,
                 from ./nbtool_config.h:720,
                 from /usr/src/tools/compat/regex.h:3,
                 from /usr/src/tools/compat/../../lib/libc/regex/regsub.c:40:
/usr/include/dirent.h:50:16: note: originally defined here
 typedef struct _dirdesc DIR;
                ^
In file included from ./nbtool_config.h:720:0,
                 from /usr/src/tools/compat/regex.h:3,
                 from /usr/src/tools/compat/../../lib/libc/regex/regsub.c:40:
/usr/src/tools/compat/compat_defs.h:268:0: warning: "dirfd" redefined
[enabled by default]
 #define dirfd(dirp)     (((struct _dirdesc *)dirp)->dd_fd)
 ^
In file included from /usr/src/tools/compat/compat_defs.h:169:0,
                 from ./nbtool_config.h:720,
                 from /usr/src/tools/compat/regex.h:3,
                 from /usr/src/tools/compat/../../lib/libc/regex/regsub.c:40:
/usr/include/dirent.h:76:0: note: this is the location of the previous
definition
 #define dirfd(dirp) ((dirp)->dd_fd)
 ^

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