genirq/irqdomain: Provide IRQ_DOMAIN_FLAG_MSI_DEVICE

Similar to marking parent MSI domains it's required to identify per device
domains. Add flag and helpers.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Reviewed-by: NKevin Tian <kevin.tian@intel.com>
Acked-by: NMarc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20221124230313.747627287@linutronix.de

include/linux/irqdomain.h

@@ -192,6 +192,9 @@ enum {
 	/* Irq domain is a MSI parent domain */
 	IRQ_DOMAIN_FLAG_MSI_PARENT	= (1 << 8),
 
+	/* Irq domain is a MSI device domain */
+	IRQ_DOMAIN_FLAG_MSI_DEVICE	= (1 << 9),
+
 	/*
 	 * Flags starting from IRQ_DOMAIN_FLAG_NONCORE are reserved
 	 * for implementation specific purposes and ignored by the
@@ -559,6 +562,11 @@ static inline bool irq_domain_is_msi_parent(struct irq_domain *domain)
 	return domain->flags & IRQ_DOMAIN_FLAG_MSI_PARENT;
 }
 
+static inline bool irq_domain_is_msi_device(struct irq_domain *domain)
+{
+	return domain->flags & IRQ_DOMAIN_FLAG_MSI_DEVICE;
+}
+
 #else	/* CONFIG_IRQ_DOMAIN_HIERARCHY */
 static inline int irq_domain_alloc_irqs(struct irq_domain *domain,
 			unsigned int nr_irqs, int node, void *arg)
@@ -610,6 +618,11 @@ static inline bool irq_domain_is_msi_parent(struct irq_domain *domain)
 	return false;
 }
 
+static inline bool irq_domain_is_msi_device(struct irq_domain *domain)
+{
+	return false;
+}
+
 #endif	/* CONFIG_IRQ_DOMAIN_HIERARCHY */
 
 #else /* CONFIG_IRQ_DOMAIN */