obsolete defflag <option> [, <option> [, ...]]
obsolete defparam <option> [, <option> [, ...]]
The two statements actually do the same thing (there could be only one),
but it makes things less cryptic that way. The optional ": deps" part of
a 'defflag' or 'defparam' still has to be dropped when it gets obsoleted.
When the user has 'options OBSOLETE_OPTION' in his configuration file, it
is ignored (that is, opt_*.h files are generated as if it wasn't there),
and the user gets a warning about it.
Bump version to 20060525.
When someone first uses that syntax in the tree, a "version 20060525"
statement should be added before its occurrence, preferably at the top
of sys/conf/files.
Suggested by Matt Thomas a few months ago.