build: iconv does not have const input parameter.

glibc was changed[1].

[1] http://sourceware.org/git/?p=glibc.git;a=commit;f=iconv/iconv.h;h=0efb48a1dfd132138a44c238b6e7f67a185a360e

Author: alonbl

configure.ac

@@ -95,34 +95,6 @@ AC_ARG_VAR([ICONV_LIBS], [linker flags for iconv])
 CPPFLAGS="${CPPFLAGS} ${ICONV_CFLAGS}"
 LIBS="${LIBS} ${ICONV_LIBS}"
 
-AC_MSG_CHECKING([iconv can handle const])
-OLD_CPPFLAGS="${CPPFLAGS}"
-test "${GCC}" = "yes" && CPPFLAGS="${CPPFLAGS} -Werror"
-AC_COMPILE_IFELSE(
-	[AC_LANG_PROGRAM(
-		[[
-#include <iconv.h>
-#include <stdlib.h>
-		]],
-		[[
-const char *test1 = NULL;
-iconv (
-	(iconv_t)0,
-	&test1,
-	NULL,
-	NULL,
-	NULL
-);
-		]]
-	)],
-	[AC_MSG_RESULT([yes])],
-	[
-		AC_MSG_RESULT([no])
-		AC_DEFINE([HAVE_OLD_ICONV], [1], [Iconv does not support const])
-	]
-)
-CPPFLAGS="${OLD_CPPFLAGS}"
-
 if test "${enable_pedantic}" = "yes"; then
 	enable_strict="yes";
 	CXXFLAGS="${CXXFLAGS} -pedantic"

mp3unicode.cpp

@@ -229,10 +229,7 @@ class Converter {
 			if (
 				iconv (
 					cd,
-#ifdef HAVE_OLD_ICONV
-					(char **)
-#endif
-					&from,
+					(char **)&from,
 					&from_size,
 					&to,
 					&to_size