doc: a->an

Part-of: <https://gitlab.freedesktop.org/monado/monado/-/merge_requests/2322>

doc/CHANGELOG.md

@@ -470,7 +470,7 @@ forward to keeping the momentum up!
     ([!2086](https://gitlab.freedesktop.org/monado/monado/merge_requests/2086))
   - The runtime name is now picked up from the CMake project description.
     ([!2089](https://gitlab.freedesktop.org/monado/monado/merge_requests/2089))
-  - Add `xrt_device::ref_space_usage` function to let a `xrt_device` know if a
+  - Add `xrt_device::ref_space_usage` function to let an `xrt_device` know if a
     reference it's powering is being used or not by any client.
     ([!2091](https://gitlab.freedesktop.org/monado/monado/merge_requests/2091),
     [!2107](https://gitlab.freedesktop.org/monado/monado/merge_requests/2107))
@@ -2978,7 +2978,7 @@ forward to keeping the momentum up!
   - OpenXR: Correctly ensure that the application has called the required get
     graphics requirements function when creating a session.
     ([!359](https://gitlab.freedesktop.org/monado/monado/merge_requests/359))
-  - OpenXR: When a `XrSession` is destroyed purge the event queue of any events
+  - OpenXR: When an `XrSession` is destroyed purge the event queue of any events
     that
     references to it so that no events gets delivered to the applications with
     stales handles.

doc/design-spaces.md

@@ -30,7 +30,7 @@ it easier for the IPC layer to implement it.
 * Where do space events come from?
   * **UNRESOLVED:** Probably will come from the space overseer.
 * Do we map all spaces one to one, like the each `XrSpace` with an offset gets
-  backed with a `xrt_space`. There is going to be a limit on spaces from the
+  backed with an `xrt_space`. There is going to be a limit on spaces from the
   point of view of the IPC layer, do we create some of them locally?
   * **RESOLVED:** While you can create a offset `xrt_space`, the offsets from
     from the `XrSpace`s are not expressed as an `xrt_space` this is to reduce