ALSA: hda: cs35l41: Fix NULL pointer dereference in cs35l41_get_acpi_mute_state()

In the Linux kernel, the following vulnerability has been resolved: ALSA: hda: cs35l41: Fix NULL pointer dereference in cs35l41_get_acpi_mute_state() Return value of a function acpi_evaluate_dsm() is dereferenced without checking for NULL, but it is usually checked for this function. acpi_evaluate_dsm() may return NULL, when acpi_evaluate_object() returns acpi_status other than ACPI_SUCCESS, so add a check to prevent the crach. Found by Linux Verification Center (linuxtesting.org) with SVACE.