Pull xen fixes from Juergen Gross:
"This contains two fixes for booting under Xen introduced during this
merge window and two fixes for older problems, where one is just much
more probable due to another merge window change"
* tag 'for-linus-4.12b-rc0c-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
xen: adjust early dom0 p2m handling to xen hypervisor behavior
x86/amd: don't set X86_BUG_SYSRET_SS_ATTRS when running under Xen
xen/x86: Do not call xen_init_time_ops() until shared_info is initialized
x86/xen: fix xsave capability setting