remove the OSS trident driver

SOUND_TRIDENT was the last PCI OSS driver, and since there's already an
ALSA driver for the same hardware we can remove it.

[muli@il.ibm.com: update CREDITS]
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Muli Ben-Yehuda <muli@il.ibm.com>
Signed-off-by: Muli Ben-Yehuda <muli@il.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>