ALSA: sscape: Fix -Wformat-truncation warning

The warning with -Wformat-truncation at sscape_upload_microcode() is
false-positive; the version number can be only a single digit, hence
fitting with the given string size.

For suppressing the warning, replace snprintf() with scnprintf().
As stated in the above, truncation doesn't matter.

Link: https://lore.kernel.org/r/20230915082802.28684-6-tiwai@suse.de


Signed-off-by: Takashi Iwai <tiwai@suse.de>