nls: have register_nls() set ->owner

pass owner explicitly to __register_nls(), make register_nls() a macro passing
THIS_MODULE as the owner argument to __register_nls().

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

nls: fix (and rename) mac NLS table files and config options

The config options in the Kconfig file (with _CODEPAGE_ in the name)
didn't match the config option name in the Makefile (no _CODEPAGE_).

And both of them were of the hard-to-read MACXYZZY variety, which made
them hard to parse for normal humans: MACROMAN easily reads as "macro
man", not as "Mac Roman".

So rename the options to be consistent, and be NLS_MAC_xyzzy. Rename
the files to be mac-xyzzy.c too, and drop the "nls" part entirely (it's
already in the directory name).

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>