ALSA: ctxfi: Fix potential OOB access in audio mixer handling

In the Linux kernel, the following vulnerability has been resolved: ALSA: ctxfi: Fix potential OOB access in audio mixer handling In the audio mixer handling code of ctxfi driver, the conf field is used as a kind of loop index, and it's referred in the index callbacks (amixer_index() and sum_index()). As spotted recently by fuzzers, the current code causes OOB access at those functions. | UBSAN: array-index-out-of-bounds in /build/reproducible-path/linux-6.17.8/sound/pci/ctxfi/ctamixer.c:347:48 | index 8 is out of range for type 'unsigned char [8]' After the analysis, the cause was found to be the lack of the proper (re-)initialization of conj field. This patch addresses those OOB accesses by adding the proper initializations of the loop indices.