[virt] Adjust spelling of initialise in code and comments

This cl updates the spelling of "initialise" to "initialize" in
the code and comments.

Test: m com.android.virt pvmfw_img
Change-Id: If0ce2a3e8188ddabd4d4e24912eb4973942bd550
diff --git a/pvmfw/src/main.rs b/pvmfw/src/main.rs
index 61e2312..ba453e7 100644
--- a/pvmfw/src/main.rs
+++ b/pvmfw/src/main.rs
@@ -95,8 +95,8 @@
     // Set up PCI bus for VirtIO devices.
     let pci_info = PciInfo::from_fdt(fdt).map_err(handle_pci_error)?;
     debug!("PCI: {:#x?}", pci_info);
-    let mut pci_root = pci::initialise(pci_info, MEMORY.lock().as_mut().unwrap()).map_err(|e| {
-        error!("Failed to initialise PCI: {e}");
+    let mut pci_root = pci::initialize(pci_info, MEMORY.lock().as_mut().unwrap()).map_err(|e| {
+        error!("Failed to initialize PCI: {e}");
         RebootReason::InternalError
     })?;