Fix signal test build

Bug: 17188805

(cherry picked from commit b9d6a55eb4eb5872739ed26ac535f0c6342e813b)

Change-Id: I0a271aa214eebe11a8442ebf68811e0d8f077d36
diff --git a/test/004-SignalTest/signaltest.cc b/test/004-SignalTest/signaltest.cc
index 3c87b48..f09fc26 100644
--- a/test/004-SignalTest/signaltest.cc
+++ b/test/004-SignalTest/signaltest.cc
@@ -21,9 +21,7 @@
 
 #include "jni.h"
 
-#if defined(__arm__) || defined(__aarch64__)
 #include <sys/ucontext.h>
-#endif
 
 static int signal_count;
 static const int kMaxSignal = 2;