Silence iconv warnings on Leopard

Apple ships a newer version of iconv with Leopard (Mac OS X 10.5/Darwin
9). Ensure that OLD_ICONV is not set on any version of Darwin in the
9.x series; this should be good for at least a couple of years, when
Darwin 10 comes out and we can invert the sense of the test to
specifically check for Darwin 7 or 8.

A more sophisticated and robust check is possible for those who use
autoconf, but not everybody does that.

Signed-off-by: Wincent Colaiuta <win@wincent.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Makefile

@@ -406,7 +406,9 @@ endif
 ifeq ($(uname_S),Darwin)
 	NEEDS_SSL_WITH_CRYPTO = YesPlease
 	NEEDS_LIBICONV = YesPlease
-	OLD_ICONV = UnfortunatelyYes
+	ifneq ($(shell expr "$(uname_R)" : '9\.'),2)
+		OLD_ICONV = UnfortunatelyYes
+	endif
 	NO_STRLCPY = YesPlease
 	NO_MEMMEM = YesPlease
 endif