message: android-mips: define PTRACE_GETREGSET in headers don't do it
  PTRACE_GETREGSET is only defined on mips only since api level 21. Define
  it ourselves, so we can compile with older platform headers.
diff: @@ -71,6 +71,9 @@ struct pt_watch_regs {
  #define IRW (I | R | W)
  +#ifndef PTRACE_GETREGSET
  +#define PTRACE_GETREGSET 0x4204
  +#endif
  struct pt_watch_regs default_watch_regs;
  using namespace lldb_private;
  