PCI/MSI: Move cached entry functions to irq core

Required to support non PCI based MSI.

[ tglx: Extracted from Jiangs patch series ]

Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

kernel/irq/msi.c

@@ -18,6 +18,19 @@
 /* Temparory solution for building, will be removed later */
 #include <linux/pci.h>
 
+void __get_cached_msi_msg(struct msi_desc *entry, struct msi_msg *msg)
+{
+	*msg = entry->msg;
+}
+
+void get_cached_msi_msg(unsigned int irq, struct msi_msg *msg)
+{
+	struct msi_desc *entry = irq_get_msi_desc(irq);
+
+	__get_cached_msi_msg(entry, msg);
+}
+EXPORT_SYMBOL_GPL(get_cached_msi_msg);
+
 #ifdef CONFIG_GENERIC_MSI_IRQ_DOMAIN
 /**
  * msi_domain_set_affinity - Generic affinity setter function for MSI domains