ALSA: echoaudio: remove redundant assignment to variable clock

The variable clock is being assigned a value that is never read,
it is being re-assigned a new value in every case in the following
switch statement. The assignment is redundant and can be removed.

Cleans up clang scan build warning:
sound/pci/echoaudio/echoaudio_3g.c:277:2: warning: Value stored
to 'clock' is never read [deadcode.DeadStores]
Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Link: https://lore.kernel.org/r/20240221113809.3410109-1-colin.i.king@gmail.comSigned-off-by: Takashi Iwai <tiwai@suse.de>

sound/pci/echoaudio/echoaudio_3g.c

@@ -274,7 +274,6 @@ static int set_sample_rate(struct echoaudio *chip, u32 rate)
 		       chip->digital_mode == DIGITAL_MODE_ADAT))
 		return -EINVAL;
 
-	clock = 0;
 	control_reg = le32_to_cpu(chip->comm_page->control_register);
 	control_reg &= E3G_CLOCK_CLEAR_MASK;