[ALSA] Remove superfluous pcm_free callbacks

sound/isa/ad1816a/ad1816a_lib.c

sound/isa/ad1848/ad1848_lib.c

sound/isa/cmi8330.c

sound/isa/cs423x/cs4231_lib.c

sound/isa/es1688/es1688_lib.c

sound/isa/es18xx.c

sound/isa/gus/gus_pcm.c

sound/isa/opti9xx/opti92x-ad1848.c

sound/isa/sb/sb16_main.c

sound/isa/sb/sb8_main.c

sound/pci/ad1889.c

sound/pci/als4000.c

sound/pci/azt3328.c

sound/pci/ca0106/ca0106_main.c

sound/pci/cmipci.c

sound/pci/cs4281.c

sound/pci/cs46xx/cs46xx_lib.c

sound/pci/emu10k1/emu10k1x.c

sound/pci/emu10k1/emupcm.c

sound/pci/emu10k1/p16v.c