ASoC: Intel: avs: Refactor and fix init_config access

In the Linux kernel, the following vulnerability has been resolved:

ASoC: Intel: avs: Refactor and fix init_config access

Existing code accesses enties found in ->init_configs array through
indexes that are part of ->config_ids array. Those two are limited by:
->num_init_configs and ->num_config_ids respectively. Using ID larger
or equal to ->num_init_configs leads to out-of-bounds access:

avs_path_module_send_init_configs()
loop:
(...) &acomp->tplg->init_configs[ids[i]]
^ out-of-bounds candidate

Rather than adding another if-statement, refactor the code. There is no
need to store the IDs, have a list of pointers to actual config-entries
instead. As the verification of ->init_config entries does not differ from
verification of other types that are part of the topology.c file, simply
reuse the code.