Add firmware protection to the environment

src/api/firmware_protection.rs

@@ -0,0 +1,6 @@
+pub trait FirmwareProtection {
+    /// Locks the firmware.
+    ///
+    /// Returns whether the operation was successful.
+    fn lock(&mut self) -> bool;
+}

src/api/mod.rs

@@ -3,4 +3,5 @@
 //! The [environment](crate::env::Env) is split into components. Each component has an API described
 //! by a trait. This module gathers the API of those components.
 
+pub mod firmware_protection;
 pub mod upgrade_storage;