dt-bindings: media: Update maintainers for st,stm32-cec.yaml

Benjamin has left the company, remove his name from maintainers.
Signed-off-by: Patrice Chotard <patrice.chotard@foss.st.com>
Link: https://lore.kernel.org/r/20211110150144.18272-4-patrice.chotard@foss.st.comSigned-off-by: Rob Herring <robh@kernel.org>

Documentation/devicetree/bindings/media/st,stm32-cec.yaml

@@ -7,7 +7,6 @@ $schema: http://devicetree.org/meta-schemas/core.yaml#
 title: STMicroelectronics STM32 CEC bindings
 
 maintainers:
-  - Benjamin Gaignard <benjamin.gaignard@st.com>
   - Yannick Fertre <yannick.fertre@st.com>
 
 properties: