media: verisilicon: rockchip: reject AV1 frames exceeding the tile capacity

In the Linux kernel, the following vulnerability has been resolved: media: verisilicon: rockchip: reject AV1 frames exceeding the tile capacity rockchip_vpu981_av1_dec_set_tile_info() indexes the tile group entry array by tile1 * tile_cols + tile0, reading up to tile_cols * tile_rows entries, lays out one descriptor per tile in the AV1_MAX_TILES tile_info buffer, and programs the real tile_cols / tile_rows into the hardware. The tile group entry control is a dynamic array sized to the number of entries userspace submitted, independent of tile_cols / tile_rows, so a frame that claims more tiles than entries reads past the array. A frame that claims more than AV1_MAX_TILES tiles also leaves the hardware programmed for more tiles than the descriptor buffer holds. Reject both in prepare_run(): tile_cols * tile_rows must not exceed the submitted entry count or AV1_MAX_TILES. The entry count is read via v4l2_ctrl_find() (ctrl->elems). This mirrors the bound the mediatek AV1 decoder already enforces.