Removed MSDOS/FAT/VFAT support; keeping CONFIG_MODULES

All options to support FAT filesystems and the VFAT extensions had no 
code associated with them and thus were removed.

That leaves only one CONFIG_NOT_YET item: CONFIG_MODULES, which is also 
a trigger for the Kconfig "tristate" system. Because removing this item 
requires also removing the Kconfig tristate capability, and we may want 
modules one day, I intend to remove CONFIG_NOT_YET but leave 
CONFIG_MODULES included, with a Big Fat Warning(TM) that it is as-yet 
unimplemented.

Jody Bruchon