ASoC: sirf-audio: Remove redundant of_match_node call

Unlike other drivers probe method, of_match_node return value
is not used or checked. This patch removes the redundant code.

Signed-off-by: Aditya Pakki <pakki001@umn.edu>
Reviewed-by: Steven Price <steven.price@arm.com>
Signed-off-by: Mark Brown <broonie@kernel.org>