staging: crypto: skein: rename enums

Linux Kernel use capitalized names for enum. To prepare skein
driver to mainline inclusion, we rename all enums to capitalized
names.

Signed-off-by: Anton Saraev <antonysaraev@gmail.com>
Reviewed-by: Jake Edge <jake@lwn.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>