misc: genwqe: card_debugfs: Demote file header from kerneldoc

Kerneldoc does not understand file headers. There is therefor
no reason for them to use the syntax.

Fixes the following W=1 kernel build warnings:

drivers/misc/genwqe/card_debugfs.c:30: warning: Function parameter or member 's' not described in 'dbg_uidn_show'
drivers/misc/genwqe/card_debugfs.c:30: warning: Function parameter or member 'regs' not described in 'dbg_uidn_show'
drivers/misc/genwqe/card_debugfs.c:30: warning: Function parameter or member 'entries' not described in 'dbg_uidn_show'

Cc: Michael Jung <[e-mail]>
Cc: Michael Ruettger <[e-mail]>
Cc: Frank Haverkamp <[e-mail]>
Cc: Joerg-Stephan Vogt <[e-mail]>
Signed-off-by: Lee Jones <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Greg Kroah-Hartman <[e-mail]>

drivers/misc/genwqe/card_debugfs.c

···
 // SPDX-License-Identifier: GPL-2.0-only
-/**
+/*
  * IBM Accelerator Family 'GenWQE'
  *
  * (C) Copyright IBM Corp. 2013