Makefile: minor improvements for Mac OS X (Darwin)

1) Instead of requesting OLD_ICONV on all Mac OS X versions except for 10.5
(which will break when 10.6 is released), exlicitly request it for versions
older than 10.5.

2) NO_STRLCPY is not needed since Mac OS X 10.2. Noticed by Benjamin Kramer.

Note that uname -r returns the underlying Darwin version, which can be mapped
to Mac OS X version at http://www.opensource.apple.com/darwinsource/Signed-off-by: NJay Soffian <jaysoffian@gmail.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Makefile

@@ -649,10 +649,12 @@ endif
 ifeq ($(uname_S),Darwin)
 	NEEDS_SSL_WITH_CRYPTO = YesPlease
 	NEEDS_LIBICONV = YesPlease
-	ifneq ($(shell expr "$(uname_R)" : '9\.'),2)
+	ifeq ($(shell expr "$(uname_R)" : '[15678]\.'),2)
 		OLD_ICONV = UnfortunatelyYes
 	endif
-	NO_STRLCPY = YesPlease
+	ifeq ($(shell expr "$(uname_R)" : '[15]\.'),2)
+		NO_STRLCPY = YesPlease
+	endif
 	NO_MEMMEM = YesPlease
 	THREADED_DELTA_SEARCH = YesPlease
 endif