MAINTAINERS: Add Kamel Bouhara as TCB counter driver maintainer

Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com>
Acked-by: Kamel Bouhara <kamel.bouhara@bootlin.com>
Acked-by: Nicolas Ferre <nicolas.ferre@microchip.com>
Link: https://lore.kernel.org/r/20201121185824.451477-1-vilhelm.gray@gmail.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>