drm/ttm: remove TTM_PAGE_FLAG_WRITE

Not used any more.
Signed-off-by: NChristian König <christian.koenig@amd.com>
Reviewed-by: NMichael J. Ruhl <michael.j.ruhl@intel.com>
Link: https://patchwork.freedesktop.org/patch/393429/

include/drm/ttm/ttm_tt.h

@@ -34,7 +34,6 @@ struct ttm_resource;
 struct ttm_buffer_object;
 struct ttm_operation_ctx;
 
-#define TTM_PAGE_FLAG_WRITE           (1 << 3)
 #define TTM_PAGE_FLAG_SWAPPED         (1 << 4)
 #define TTM_PAGE_FLAG_ZERO_ALLOC      (1 << 6)
 #define TTM_PAGE_FLAG_DMA32           (1 << 7)