refactor(userspace): split syscall/fat16/ext4 by concern; trim comments

crates/drivers/input/virtio/src/lib.rs

@@ -31,10 +31,8 @@ pub struct VirtioInputDevice {
 }
 
 impl VirtioInputDevice {
-    /// Takes over the input device whose MMIO region `mmio` names: maps it,
-    /// allocates the queue and event buffers, resets the device onto them
-    /// and hands it every buffer. `None` if it is not a virtio input
-    /// device or a step fails.
+    /// Takes over the virtio input device behind `mmio`. `None` if it is
+    /// not one or any step fails.
     pub fn try_new(mmio: types::bounded::CapSlot) -> Option<Self> {
         libkos::device::map_mmio(mmio, INPUT_MMIO_VA).ok()?;
         let regs = MmioInput;