Unbreak on little-endian archs

--- libexfat/platform.h.orig	Sat Aug  6 08:50:22 2016
+++ libexfat/platform.h	Sat Aug  6 08:50:40 2016
@@ -49,9 +49,9 @@
 #elif defined(__FreeBSD__) || defined(__DragonFlyBSD__) || defined(__NetBSD__) || defined(__OpenBSD__)
 
 #include <sys/endian.h>
-#define exfat_bswap16(x) bswap16(x)
-#define exfat_bswap32(x) bswap32(x)
-#define exfat_bswap64(x) bswap64(x)
+#define exfat_bswap16(x) swap16(x)
+#define exfat_bswap32(x) swap32(x)
+#define exfat_bswap64(x) swap64(x)
 #define EXFAT_BYTE_ORDER _BYTE_ORDER
 #define EXFAT_LITTLE_ENDIAN _LITTLE_ENDIAN
 #define EXFAT_BIG_ENDIAN _BIG_ENDIAN
