counter: microchip-tcb-capture: Tidy up a false kernel-doc /** marking.

Deals with
W=1 warning This comment starts with '/**', but isn't a kernel-doc comment.
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Cc: Kamel Bouhara <kamel.bouhara@bootlin.com>
Cc: William Breathitt Gray <vilhelm.gray@gmail.com>
Acked-by: William Breathitt Gray <vilhelm.gray@gmail.com>
Link: https://lore.kernel.org/r/20210930170347.101153-1-jic23@kernel.org

drivers/counter/microchip-tcb-capture.c

 // SPDX-License-Identifier: GPL-2.0-only
-/**
+/*
  * Copyright (C) 2020 Microchip
  *
  * Author: Kamel Bouhara <kamel.bouhara@bootlin.com>