crypto: caam - Move debugfs fops into standalone file

Currently the debugfs fops are defined in caam/intern.h.  This causes
problems because it creates identical static functions and variables
in multiple files.  It also creates warnings when those files don't
use the fops.

This patch moves them into a standalone file, debugfs.c.

It also removes unnecessary uses of ifdefs on CONFIG_DEBUG_FS.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
[Moved most of debugfs-related operations into debugfs.c.]
Signed-off-by: Horia Geantă <horia.geanta@nxp.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>