PR #336: since we can't use function overriding (due to problems with it on

OSX) always include the _json_c_strerror function but only enable it with a flag
 during tests.

configure.ac

@@ -23,22 +23,6 @@ else
   AC_MSG_RESULT([RDRAND Hardware RNG Hash Seed disabled. Use --enable-rdrand to enable])
 fi
 
-AC_ARG_ENABLE(strerror-override,
- AS_HELP_STRING([--enable-strerror-override],
-   [Override strerror() function with internal version.]),
-[if test x$enableval = xyes; then
-  enable_strerror_override=yes
-  AC_DEFINE(ENABLE_STRERROR_OVERRIDE, 1, [Override strerror() with internal version])
-fi])
-
-AM_CONDITIONAL([ENABLE_STRERROR_OVERRIDE], [test "x$enable_strerror_override" = "xyes"])
-
-if test "x$enable_strerror_override" = "xyes"; then
-  AC_MSG_RESULT([Overriding `strerror()` function with internal version])
-else
-  AC_MSG_RESULT([Using libc's `strerror()` function])
-fi
-
 # enable silent build by default
 m4_ifdef([AM_SILENT_RULES], [AM_SILENT_RULES([yes])])