Silence the annoying warning in MSVC about undeclared bswap

 ..\..\src\cborparser.c(149): warning C4013: '_byteswap_ushort' undefined; assuming extern returning int
 ..\..\src\cborparser.c(156): warning C4013: '_byteswap_ulong' undefined; assuming extern returning int
 ..\..\src\cborparser.c(163): warning C4013: '_byteswap_uint64' undefined; assuming extern returning int

This apparently also fixes the unit test failures.

 FAIL!  : tst_Parser::fixed(UINT32_MAX+1) Compared values are not the same
   Actual   (decoded) : "0_3"
   Expected (expected): "4294967296"
 .\tst_parser.cpp(233) : failure location

Signed-off-by: Thiago Macieira <thiago.macieira@intel.com>

Author: thiagomacieira

src/compilersupport_p.h

@@ -125,6 +125,7 @@
 #  include <sys/byteorder.h>
 #elif defined(_MSC_VER)
 /* MSVC, which implies Windows, which implies little-endian and sizeof(long) == 4 */
+#  include <stdlib.h>
 #  define cbor_ntohll       _byteswap_uint64
 #  define cbor_htonll       _byteswap_uint64
 #  define cbor_ntohl        _byteswap_ulong