ALSA: seq: Simplify internal command operation from OSS layer

ALSA: seq: Simplify internal command operation from OSS layer

snd_seq_client_ioctl_lock() and *_unlock() are used only from a single
function of the OSS layer, and it's just to wrap the call of
snd_seq_kernel_client_ctl().

Provide another variant of snd_seq_kernel_client_ctl() that takes the
locks internally and drop the ugly snd_seq_client_ioctl_lock() and
*_unlock() implementations, instead.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
Link: https://patch.msgid.link/20250827080520.7544-2-tiwai@suse.de