bsp: rockchip: fix CAN-FD bit timing copy size

[Old-Ding]

What this PR does

Fixes the Rockchip CAN-FD RT_CAN_CMD_SET_BITTIMING handler to copy the full struct rt_can_bit_timing entries from timing->items.

The current code uses sizeof(&timing->items[n]), which is the size of a pointer, when copying into can->config.can_timing and can->config.canfd_timing. That can leave part of each timing structure unchanged. Other CAN drivers copy the full items[n] entry.

Verification

• git diff --check
• git show --stat --check --format=fuller HEAD
• git ls-files --eol -- bsp/rockchip/dm/can/canfd-rockchip.c
• rg -n sizeof\s*\(&timing->items bsp/rockchip/dm/can/canfd-rockchip.c returns no matches

I could not run an RT-Thread build locally because this Windows environment does not have scons, gcc, or arm-none-eabi-gcc installed.

Generated-by: OpenAI Codex

[github-actions]

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