kern/47909: ufs symbol pollution

[dholland%NetBSD.org@localhost]

>Number:         47909
>Category:       kern
>Synopsis:       ufs symbol pollution
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    kern-bug-people
>State:          open
>Class:          change-request
>Submitter-Id:   net
>Arrival-Date:   Sat Jun 08 21:25:00 +0000 2013
>Originator:     David A. Holland
>Release:        current of 20130607
>Organization:
>Environment:
n/a
>Description:

The ufs headers expose a lot of symbols that do not begin with ufs_ or
UFS_; this is unfriendly to other file systems, because there are a
number of tools that support multiple file system types and want to be
able to include headers from all of them in the same translation unit.

I've already fixed a number of these; here are some more that have
come to light: 

(1)
DIRBLKSIZ
DIRECTSIZ
DIRSIZ
OLDDIRFMT
NEWDIRFMT

(2)
IFTODT
DTTOIF
IFMT, IFIFO, IFCHR, etc.
DT_UNKNOWN, DT_FIFO, DT_CHR, etc.

The DT_ ones are particularly problematic as they duplicate the
FS-independent symbols from <dirent.h>.

>How-To-Repeat:

>Fix: