thermal: adc-tm: Fix match table description

Due to an error in the specification of the multiple compatible strings
in the match table, nodes defined with compatible string "adc-tm5-iio"
failed to probe. Fix this.

Change-Id: I6cf544b202dfb0773215aeaeae8a12bae5b79dde
Signed-off-by: Guru Das Srinagesh <gurus@codeaurora.org>