MAINTAINERS: Update maintainer for LT8912B DRM HDMI bridge

MAINTAINERS: Update maintainer for LT8912B DRM HDMI bridge

Update the maintainer from Adrien to Francesco.  Adrien is not
interested in maintaining this driver anymore, Francesco has access to
various hardware devices using this component and the vendor
documentation.

Cc: Adrien Grassein <adrien.grassein@gmail.com>
Signed-off-by: Francesco Dolcini <francesco.dolcini@toradex.com>
Reviewed-by: Luca Ceresoli <luca.ceresoli@bootlin.com>
Acked-by: Adrien Grassein <adrien.grassein@gmail.com>
Acked-by: Neil Armstrong <neil.armstrong@linaro.org>
Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org>
Link: https://patch.msgid.link/20260430085344.34271-1-francesco@dolcini.it