Revert "staging: vchiq_arm: Create keep-alive thread during probe"

Revert "staging: vchiq_arm: Create keep-alive thread during probe"

The commit 86bc88217006 ("staging: vchiq_arm: Create keep-alive thread
during probe") introduced a regression for certain configurations,
which doesn't have a VCHIQ user. This results in a unused and hanging
keep-alive thread:

  INFO: task vchiq-keep/0:85 blocked for more than 120 seconds.
        Not tainted 6.12.34-v8-+ #13
  "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
  task:vchiq-keep/0    state:D stack:0 pid:85    tgid:85    ppid:2
  Call trace:
   __switch_to+0x188/0x230
   __schedule+0xa54/0xb28
   schedule+0x80/0x120
   schedule_preempt_disabled+0x30/0x50
   kthread+0xd4/0x1a0
   ret_from_fork+0x10/0x20

Fixes: 86bc88217006 ("staging: vchiq_arm: Create keep-alive thread during probe")
Reported-by: Maíra Canal <mcanal@igalia.com>
Closes: https://lore.kernel.org/linux-staging/ba35b960-a981-4671-9f7f-060da10feaa1@usp.br/
Cc: stable@kernel.org
Signed-off-by: Stefan Wahren <wahrenst@gmx.net>
Reviewed-by: Maíra Canal <mcanal@igalia.com>
Link: https://lore.kernel.org/r/20250715161108.3411-3-wahrenst@gmx.net
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>