i2c: mediatek: move dma reset before i2c reset

The i2c driver default do dma reset after i2c reset, but sometimes
i2c reset will trigger dma tx2rx, then apdma write data to dram
which has been i2c_put_dma_safe_msg_buf(kfree). Move dma reset
before i2c reset in mtk_i2c_init_hw to fix it.

Signed-off-by: Qii Wang <qii.wang@mediatek.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>