Fix compilation on newer NetBSD systems

NetBSD >=2.0 has iconv() in libc.  A libiconv is not required and
does not exist.

See: http://netbsd.gw.com/cgi-bin/man-cgi?iconv+3+NetBSD-2.0

[jc: with a bit of simplification later discussed on the list.]
Signed-off-by: NDennis Stosberg <dennis@stosberg.net>
Signed-off-by: NJunio C Hamano <junkio@cox.net>

Makefile

@@ -281,7 +281,9 @@ ifeq ($(uname_S),OpenBSD)
 	ALL_LDFLAGS += -L/usr/local/lib
 endif
 ifeq ($(uname_S),NetBSD)
-	NEEDS_LIBICONV = YesPlease
+	ifeq ($(shell expr "$(uname_R)" : '[01]\.'),2)
+		NEEDS_LIBICONV = YesPlease
+	endif
 	ALL_CFLAGS += -I/usr/pkg/include
 	ALL_LDFLAGS += -L/usr/pkg/lib -Wl,-rpath,/usr/pkg/lib
 endif