Update entry for MediaTek PCIe controller, add Jianjun Wang
as MediaTek PCI co-maintainer.

Link: https://lore.kernel.org/r/20210420061723.989-8-jianjun.wang@mediatek.comSigned-off-by: NJianjun Wang <jianjun.wang@mediatek.com>
Signed-off-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: NRyder Lee <ryder.lee@mediatek.com>