orangefs: Move s_kmod_keyword_mask_map to orangefs-debugfs.c

orangefs: Move s_kmod_keyword_mask_map to orangefs-debugfs.c

Attempting to build orangefs with W=1 currently reports errors like:

In file included from ../fs/orangefs/protocol.h:287,
                 from ../fs/orangefs/waitqueue.c:16:
../fs/orangefs/orangefs-debug.h:86:18: error: ‘num_kmod_keyword_mask_map’ defined but not used [-Werror=unused-const-variable=]

Move num_kmod_keyword_mask_map, s_kmod_keyword_mask_map and
struct __keyword_mask_s to orangefs-debugfs.c which is the only file
they're used in.

Signed-off-by: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Link: https://lore.kernel.org/r/20250305204734.1475264-3-willy@infradead.org
Tested-by: Mike Marshall <hubcap@omnibond.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>