msix: add api to access msix message

Will be used by virtio pci.
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>

hw/pci/msix.c

@@ -27,7 +27,7 @@
 #define MSIX_ENABLE_MASK (PCI_MSIX_FLAGS_ENABLE >> 8)
 #define MSIX_MASKALL_MASK (PCI_MSIX_FLAGS_MASKALL >> 8)
 
-static MSIMessage msix_get_message(PCIDevice *dev, unsigned vector)
+MSIMessage msix_get_message(PCIDevice *dev, unsigned vector)
 {
     uint8_t *table_entry = dev->msix_table + vector * PCI_MSIX_ENTRY_SIZE;
     MSIMessage msg;

hw/pci/msix.h

@@ -5,6 +5,7 @@
 #include "hw/pci/pci.h"
 
 void msix_set_message(PCIDevice *dev, int vector, MSIMessage msg);
+MSIMessage msix_get_message(PCIDevice *dev, unsigned int vector);
 int msix_init(PCIDevice *dev, unsigned short nentries,
               MemoryRegion *table_bar, uint8_t table_bar_nr,
               unsigned table_offset, MemoryRegion *pba_bar,