Remove deprecated WITH_HOST_DALVIK.

Bug: 13751317
Fix the Mac build:
 - disable x86 selector removal that causes OS/X 10.9 kernel panics,
 - madvise don't need does zero memory on the Mac, factor into MemMap
   routine,
 - switch to the elf.h in elfutils to avoid Linux kernel dependencies,
 - we can't rely on exclusive_owner_ being available from other pthread
   libraries so maintain our own when futexes aren't available (we
   can't rely on the OS/X 10.8 hack any more),
 - fix symbol naming in assembly code,
 - work around C library differences,
 - disable backtrace in DumpNativeStack to avoid a broken libbacktrace
   dependency,
 - disable main thread signal handling logic,
 - align the stack in stub_test,
 - use $(HOST_SHLIB_SUFFIX) rather than .so in host make file variables.

Not all host tests are passing on the Mac with this change. dex2oat
works as does running HelloWorld.
Change-Id: I5a232aedfb2028524d49daa6397a8e60f3ee40d3
diff --git a/runtime/runtime_linux.cc b/runtime/runtime_linux.cc
index 960d332..46ee274 100644
--- a/runtime/runtime_linux.cc
+++ b/runtime/runtime_linux.cc
@@ -327,7 +327,7 @@
     while (true) {
     }
   }
-
+#ifdef __linux__
   // Remove our signal handler for this signal...
   struct sigaction action;
   memset(&action, 0, sizeof(action));
@@ -336,6 +336,9 @@
   sigaction(signal_number, &action, NULL);
   // ...and re-raise so we die with the appropriate status.
   kill(getpid(), signal_number);
+#else
+  exit(EXIT_FAILURE);
+#endif
 }
 
 void Runtime::InitPlatformSignalHandlers() {