sound: soc: dapm: Update adc dapm widget priority

Adc dapm widget priority is getting overwritten with
a lower priority because of dapm up sequence having
two values for same widget type. Remove the second
assignement to fix adc dapm setting issues.

Change-Id: I01d4cbffe55e81ef2d1e2455d8598438616e31ae
Signed-off-by: Karthikeyan Mani <kmani@codeaurora.org>