Input: cpcap-pwrbutton - remove initial kernel-doc notation

Change the beginning "/**" in the file to "/*" since it is not a
kernel-doc comment. This prevents a kernel-doc warning:

drivers/input/misc/cpcap-pwrbutton.c:2: warning: This comment starts with '/**', but isn't a kernel-doc comment. Refer Documentation/doc-guide/kernel-doc.rst
 * CPCAP Power Button Input Driver
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Reviewed-by: Sebastian Reichel <sebastian.reichel@collabora.com>
Link: https://lore.kernel.org/r/20230703230005.14877-1-rdunlap@infradead.orgSigned-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

drivers/input/misc/cpcap-pwrbutton.c

-/**
+/*
  * CPCAP Power Button Input Driver
  *
  * Copyright (C) 2017 Sebastian Reichel <sre@kernel.org>