Fix clippy errors

Signed-off-by: Tyler Fanelli <tfanelli@redhat.com>

src/devices/src/bus.rs

@@ -69,7 +69,7 @@ impl Ord for BusRange {
 
 impl PartialOrd for BusRange {
     fn partial_cmp(&self, other: &BusRange) -> Option<Ordering> {
-        self.0.partial_cmp(&other.0)
+        Some(self.cmp(other))
     }
 }
 

src/libkrun/src/lib.rs

@@ -8,6 +8,7 @@ use std::env;
 use std::ffi::CStr;
 #[cfg(target_os = "linux")]
 use std::ffi::CString;
+use std::fmt::Write;
 #[cfg(feature = "net")]
 use std::os::fd::RawFd;
 #[cfg(not(feature = "tee"))]
@@ -677,9 +678,10 @@ pub unsafe extern "C" fn krun_set_exec(
             }
         }
     } else {
-        env::vars()
-            .map(|(key, value)| format!(" {key}=\"{value}\""))
-            .collect()
+        env::vars().fold(String::new(), |mut output, (key, value)| {
+            let _ = write!(output, " {key}=\"{value}\"");
+            key
+        })
     };
 
     match CTX_MAP.lock().unwrap().entry(ctx_id) {
@@ -708,9 +710,10 @@ pub unsafe extern "C" fn krun_set_env(ctx_id: u32, c_envp: *const *const c_char)
             }
         }
     } else {
-        env::vars()
-            .map(|(key, value)| format!(" {key}=\"{value}\""))
-            .collect()
+        env::vars().fold(String::new(), |mut output, (key, value)| {
+            let _ = write!(output, " {key}=\"{value}\"");
+            key
+        })
     };
 
     match CTX_MAP.lock().unwrap().entry(ctx_id) {

src/vmm/src/builder.rs

@@ -353,7 +353,7 @@ pub fn build_microvm(
     };
 
     #[cfg(not(feature = "tee"))]
-    let mut vm = setup_vm(&guest_memory)?;
+    let vm = setup_vm(&guest_memory)?;
 
     #[cfg(feature = "tee")]
     let (kvm, mut vm) = {
@@ -482,7 +482,7 @@ pub fn build_microvm(
     // while on aarch64 we need to do it the other way around.
     #[cfg(target_arch = "x86_64")]
     {
-        setup_interrupt_controller(&mut vm)?;
+        setup_interrupt_controller(&vm)?;
         attach_legacy_devices(&vm, &mut pio_device_manager)?;
 
         vcpus = create_vcpus_x86_64(
@@ -795,7 +795,7 @@ pub(crate) fn setup_vm(
 
 /// Sets up the irqchip for a x86_64 microVM.
 #[cfg(target_arch = "x86_64")]
-pub fn setup_interrupt_controller(vm: &mut Vm) -> std::result::Result<(), StartMicrovmError> {
+pub fn setup_interrupt_controller(vm: &Vm) -> std::result::Result<(), StartMicrovmError> {
     vm.setup_irqchip()
         .map_err(Error::Vm)
         .map_err(StartMicrovmError::Internal)