[kernel-doc] fix various DocBook build problems/warnings

Most serious is fixing include/sound/pcm.h, which breaks the DocBook
build.

The other stuff is just filling in things that cause warnings.

Documentation/DocBook/mcabook.tmpl

···
 
   <chapter id="pubfunctions">
      <title>Public Functions Provided</title>
-!Earch/i386/kernel/mca.c
+!Edrivers/mca/mca-legacy.c
   </chapter>
 
   <chapter id="dmafunctions">

drivers/net/wan/syncppp.c

···
  *	@skb:	The buffer to process
  *	@dev:	The device it arrived on
  *	@p: Unused
+ *	@orig_dev: Unused
  *
  *	Protocol glue. This drives the deferred processing mode the poorer
  *	cards use. This can be called directly by cards that do not have

drivers/scsi/libata-core.c

···
  *	@ap: port to read/write
  *	@buf: data buffer
  *	@buflen: buffer length
- *	@do_write: read/write
+ *	@write_data: read/write
  *
  *	Transfer data from/to the device data register by MMIO.
  *
···
  *	@ap: port to read/write
  *	@buf: data buffer
  *	@buflen: buffer length
- *	@do_write: read/write
+ *	@write_data: read/write
  *
  *	Transfer data from/to the device data register by PIO.
  *

include/sound/pcm.h

···
 int snd_pcm_format_linear(snd_pcm_format_t format);
 int snd_pcm_format_little_endian(snd_pcm_format_t format);
 int snd_pcm_format_big_endian(snd_pcm_format_t format);
-/**
+/*
  * snd_pcm_format_cpu_endian - Check the PCM format is CPU-endian
  * @format: the format to check
  *

kernel/sched.c

···
 
 /**
  * finish_task_switch - clean up after a task-switch
+ * @rq: runqueue associated with task-switch
  * @prev: the thread we just switched away from.
  *
  * finish_task_switch must be called after the context switch, paired