Include this header to define _LITTLE_ENDIAN

--- synergy-1.7.4-stable/src/micro/uSynergy.h.~1~	2015-08-08 01:56:23.000000000 +0300
+++ synergy-1.7.4-stable/src/micro/uSynergy.h	2015-08-18 13:03:30.868265690 +0300
@@ -25,6 +25,7 @@
    distribution.
 */
 #include <stdint.h>
+#include <sys/isa_defs.h>
 
 #ifdef __cplusplus
 extern "C" {
@@ -46,9 +47,9 @@
 	#error "Can't define both USYNERGY_LITTLE_ENDIAN and USYNERGY_BIG_ENDIAN"
 #elif !defined(USYNERGY_LITTLE_ENDIAN) && !defined(USYNERGY_BIG_ENDIAN)
 	/* Attempt to auto detect */
-	#if defined(__LITTLE_ENDIAN__) || defined(LITTLE_ENDIAN) || (_BYTE_ORDER == _LITTLE_ENDIAN)
+	#if defined(__LITTLE_ENDIAN__) || defined(LITTLE_ENDIAN) || defined(_LITTLE_ENDIAN)
 		#define USYNERGY_LITTLE_ENDIAN
-	#elif defined(__BIG_ENDIAN__) || defined(BIG_ENDIAN) || (_BYTE_ORDER == _BIG_ENDIAN)
+	#elif defined(__BIG_ENDIAN__) || defined(BIG_ENDIAN) || defined(_BIG_ENDIAN)
 		#define USYNERGY_BIG_ENDIAN
 	#else
 		#error "Can't detect endian-nes, please defined either USYNERGY_LITTLE_ENDIAN or USYNERGY_BIG_ENDIAN";