x86/dpci: EOI interrupt regardless of its masking status

x86/dpci: EOI interrupt regardless of its masking status

Modify hvm_pirq_eoi to always EOI the interrupt if required, instead
of not doing such EOI if the interrupt is routed through the vIO-APIC
and the entry is masked at the time the EOI is performed.

Further unmask of the vIO-APIC pin won't EOI the interrupt, and thus
the guest OS has to wait for the timeout to expire and the automatic
EOI to be performed.

This allows to simplify the helpers and drop the vioapic_redir_entry
parameter from all of them.

Fixes: ccfe4e08455 ('Intel vt-d specific changes in arch/x86/hvm/vmx/vtd.')
Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>