RFC: merging the quota source files

[Christoph Hellwig]

Hi,

I've started a bit work on the quota code, and the split between the
implementation files is rather annoying.  I'd suggest we merge at least
xfs_dquot.c and xfs_qm.c into a single file, as there is no visible
split.  Given how small and useless xfs_qm_bhv.c is I'd throw it in.

As a second pass I'd also like to kill xfs_qm_syscalls.c and merge
it into the new xfs_qm.c/xfs_dquot.c for the low-level helpers, and
xfs_quotaops.c for high-level code that deals directly with the Linux
interface.

Does this a) sound good to others, and b) does anyone have a preference
for the name of the new quota implementation file?