drm/amd/display: fix typo: liason -> liaison

Signed-off-by: NDiego Viola <diego.viola@gmail.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c

@@ -121,7 +121,7 @@ MODULE_FIRMWARE(FIRMWARE_NAVI12_DMCU);
  * DOC: overview
  *
  * The AMDgpu display manager, **amdgpu_dm** (or even simpler,
- * **dm**) sits between DRM and DC. It acts as a liason, converting DRM
+ * **dm**) sits between DRM and DC. It acts as a liaison, converting DRM
  * requests into DC requests, and DC responses into DRM responses.
  *
  * The root control structure is &struct amdgpu_display_manager.