x86: Reclaim TIF_IA32 and TIF_X32

Now that these flags are no longer used, reclaim those TIF bits.

Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20201004032536.1229030-11-krisman@collabora.com