ALSA: scarlett2: Fix mixed declarations and code warning

In scarlett2_compressor_ctl_put(), move the declaration of param to
the beginning of the function to avoid mixed declarations and code.

Signed-off-by: Geoffrey D. Bennett <g@b4.vu>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Link: https://patch.msgid.link/ede84092737fa2ca7e94371135cc1e42f1731e84.1727971672.git.g@b4.vu