drm/i915/gem/i915_gem_ttm_move: Fix typo

The mapings should be replaced by mappings.

Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Deming Wang <wangdeming@inspur.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240513061451.1627-1-wangdeming@inspur.com


Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>