Ada build now requires gnatmake?

[Joe Buck]

>     I just did an update and tried a bootstrap, and it seems that gnatmake
>     is used to build the Ada compiler, specifically to build treeprs.ads,
>     einfo.h, sinfo.h, and nmake.adb.  I thought bootstrapping was only
>     supposed to require the compiler and gnatbind.

Kenner writes:

> Those files are in the tree, but you may have to do a "touch" if they are older
> than what they depend on.

Perhaps contrib/gcc_update should be updated to take care of this?  It
already does the same for other such files where the derived file is
in the tree.