Solaris: Use OLD_ICONV to avoid compile warnings

Solaris systems use the old styled iconv(3) call and therefore
the OLD_ICONV variable should be set. Otherwise we get annoying compile
warnings.

Signed-off-by: David Soria Parra <dsp@php.net>
Acked-by: Jeff King <peff@peff.net>
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

Makefile

@@ -637,6 +637,7 @@ ifeq ($(uname_S),SunOS)
 	NO_MEMMEM = YesPlease
 	NO_HSTRERROR = YesPlease
 	NO_MKDTEMP = YesPlease
+	OLD_ICONV = UnfortunatelyYes
 	ifeq ($(uname_R),5.8)
 		NEEDS_LIBICONV = YesPlease
 		NO_UNSETENV = YesPlease