Remove some code which is unneeded if CONFIG_PM=n.
* Make suspend/resume registration look like the rest of drivers:
#ifdef CONFIG_PM in struct pci_driver, prototypes, actual hooks.
* Drop CS46XX_ACPI_SUPPORT. It logically duplicated CONFIG_PM. It was
hardcoded to 1 approx forever (ALSA merge just moved driver to
sound/oss/).
* After previous point, sound/oss/cs46xxpm-24.h removed as being useless.
* As side effect selling (unused) static inline functions as suspend/resume
hooks funkiness removed too.