vm-device, pci, devices: Remove InterruptSourceGroup::{un}mask

The calls to these functions are always preceded by a call to
InterruptSourceGroup::update(). By adding a masked boolean to that
function call it possible to remove 50% of the calls to the
KVM_SET_GSI_ROUTING ioctl as the the update will correctly handle the
masked or unmasked case.

This causes the ioctl to disappear from the perf report for a boot of
the VM.

Signed-off-by: Rob Bradford <robert.bradford@intel.com>

devices/src/ioapic.rs

@@ -367,19 +367,13 @@ impl Ioapic {
         };
 
         self.interrupt_source_group
-            .update(irq as InterruptIndex, InterruptSourceConfig::MsiIrq(config))
+            .update(
+                irq as InterruptIndex,
+                InterruptSourceConfig::MsiIrq(config),
+                interrupt_mask(entry) == 1,
+            )
             .map_err(Error::UpdateInterrupt)?;
 
-        if interrupt_mask(entry) == 1 {
-            self.interrupt_source_group
-                .mask(irq as InterruptIndex)
-                .map_err(Error::MaskInterrupt)?;
-        } else {
-            self.interrupt_source_group
-                .unmask(irq as InterruptIndex)
-                .map_err(Error::UnmaskInterrupt)?;
-        }
-
         Ok(())
     }
 }