ASoC: qcom: topology: Constify pointed snd_soc_tplg_dapm_widget

ASoC: qcom: topology: Constify pointed snd_soc_tplg_dapm_widget

Several functions in topology.c receive pointers to 'struct
snd_soc_tplg_dapm_widget' and do not modify their contents.  Constify
the pointers for self-explanatory code (pointed memory is not modified
by the function) and a bit safer code.

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@oss.qualcomm.com>
Link: https://patch.msgid.link/20251219-b4-container-of-const-asoc-qcom-v2-4-05fd2ecc06fe@oss.qualcomm.com
Signed-off-by: Mark Brown <broonie@kernel.org>