x86/mm: Use flags for _put_page_type rather than a boolean

x86/mm: Use flags for _put_page_type rather than a boolean

This is in mainly in preparation for _put_page_type taking the
partial_flags value in the future.  It also makes it easier to read in
the caller (since you see a flag name rather than `true` or `false`).

No functional change intended.

This is part of XSA-299.

Reported-by: George Dunlap <george.dunlap@citrix.com>
Signed-off-by: George Dunlap <george.dunlap@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
master commit: 0121588ec0f6950ed65d906d860df49be2c8e655
master date: 2019-10-31 16:12:53 +0100