x86/vdso: Clean up remnants of VDSO32_NOTE_MASK

x86/vdso: Clean up remnants of VDSO32_NOTE_MASK

VDSO32_NOTE_MASK is not used or provided anymore, remove it.

Fixes: a13f2ef168cb ("x86/xen: remove 32-bit Xen PV guest support")
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Juergen Gross <jgross@suse.com>
Link: https://patch.msgid.link/20260330-vdso-x86-vdso32_note_mask-v1-1-2f5c473327bf@linutronix.de