vfio: fix vfio device fail to initialize issue for 64k page size

Currently, vfio device fails to initialize as the msix-cap region in BAR
is mapped as RW region.

To resolve the initialization issue, this commit avoids mapping the
msix-cap region in the BAR. However, this solution introduces another
problem where aligning the msix table offset in the BAR to the page
size may cause overlap with the MMIO RW region, leading to reduced
performance. By enlarging the entire region in the BAR and relocating
the msix table to achieve page size alignment, this problem can be
overcomed effectively.

Fixes: #5292
Signed-off-by: Jianyong Wu <jianyong.wu@arm.com>

pci/src/msix.rs

@@ -511,6 +511,16 @@ impl MsixCap {
         self.pba & 0xffff_fff8
     }
 
+    pub fn table_set_offset(&mut self, addr: u32) {
+        self.table &= 0x7;
+        self.table += addr;
+    }
+
+    pub fn pba_set_offset(&mut self, addr: u32) {
+        self.pba &= 0x7;
+        self.pba += addr;
+    }
+
     pub fn table_bir(&self) -> u32 {
         self.table & 0x7
     }