Jens' email address bounces, so move his name and entry to CREDITS.

Signed-off-by: Joe Perches <[email protected]>
Cc: Ishizaki Kou <[email protected]>
Cc: Jens Osterkamp <[email protected]>
Cc: Benjamin Herrenschmidt <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>