quick fix for arm builds

rdtsc is an x86 assembly instruction to read the processors

https://www.spinics.net/lists/fedora-devel/msg224266.html

x265-detect_cpu_armhfp.patch

@@ -42,3 +42,18 @@ diff -up x265_2.2/source/CMakeLists.txt.orig x265_2.2/source/CMakeLists.txt
  else()
      message(STATUS "CMAKE_SYSTEM_PROCESSOR value `${CMAKE_SYSTEM_PROCESSOR}` is unknown")
      message(STATUS "Please add this value near ${CMAKE_CURRENT_LIST_FILE}:${CMAKE_CURRENT_LIST_LINE}")
+--- x265_v2.6/source/test/testharness.h.orig	2017-12-30 22:27:49.827620181 +0000
++++ x265_v2.6/source/test/testharness.h	2017-12-30 22:30:53.239500941 +0000
+@@ -70,9 +70,10 @@ protected:
+ #include <intrin.h>
+ #elif (!defined(__APPLE__) && (defined (__GNUC__) && (defined(__x86_64__) || defined(__i386__))))
+ #include <x86intrin.h>
+-#elif ( !defined(__APPLE__) && defined (__GNUC__) && defined(__ARM_NEON__))
+-#include <arm_neon.h>
+ #elif defined(__GNUC__)
++#if ( !defined(__APPLE__) && defined(__ARM_NEON__))
++#include <arm_neon.h>
++#endif
+ /* fallback for older GCC/MinGW */
+ static inline uint32_t __rdtsc(void)
+ {