Adding gcc config header.

gcc-xomb/gcc/config/xomb.h

@@ -0,0 +1,11 @@
+#undef TARGET_OS_CPP_BUILTINS
+#define TARGET_OS_CPP_BUILTINS()      \
+  do {                                \
+    builtin_define_std ("xomb");      \
+    builtin_define_std ("unix");      \
+    builtin_assert ("system=xomb");   \
+    builtin_assert ("system=unix");   \
+  } while(0);
+
+#undef TARGET_VERSION
+#define TARGET_VERSION fprintf(stderr, " (x86_64 xomb)");