x86/shadow: Avoid raising faults behind the emulators back

x86/shadow: Avoid raising faults behind the emulators back

Use x86_emul_{hw_exception,pagefault}() rather than
{pv,hvm}_inject_page_fault() and hvm_inject_hw_exception() to cause raised
faults to be known to the emulator.  This requires altering the callers of
x86_emulate() to properly re-inject the event.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Tim Deegan <tim@xen.org>
Reviewed-by: Jan Beulich <jbeulich@suse.com>