vchoi_fork

[svn-r4231] Purpose:
    Bug fix.
Description:
    On some systems (linux when not using gcc) the 'dev_t' is not actually
    a scalar variable.  This causes the code which compares dev_t's in
    the file drivers to not compile.
Solution:
    Detect this and set the DEV_T_IS_SCALAR flag so we can code around it
    in the file drivers.
Platforms tested:
    FreeBSD 4.3 (hawkwind), Linux 2.4.2 (chiba city cluster at Argonne)