ALSA: echoaudio: remove redundant assignment to variable i

The variable i is being assigned a value that is never read, it
is being re-assigned in the following for-loop. The assignment is
redundant and can be removed.

Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Link: https://lore.kernel.org/r/20220405135412.199251-1-colin.i.king@gmail.com


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