x86: thread_info: merge tif masks

The TIF masks are basically the same. x86_32 also has _TIF_SYSCALL_EMU which is
zero for the 64 bit case. The tif masks become the same.

x86_64 has an additional _TIF_DONOTIFY_MASK. Does not hurt for the 32 bit case
since it is only used in x86_64 arch code.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>