[Ada] some parallel build fixes

[guerby@acm.org]

> A parallel make still fails, because not all of the Ada source
> dependencies are described in the makefile.  We should either enter
> them all by hand or assume gnatmake.  I prefer the former myself,
> since it makes it easier to bootstrap a new target.

IIRC, at ACT there was a little script that used "gnatmake -M" to
update the Ada dependencies in the Makefile after the automatic
nightly build (-M makes gnatmake read the ali files, and generate
Makefile dependencies). 

Could someone at ACT forward us the script if it's still there?

Otherwise I'll try to cook it up, a bit of sed
s,../../gcc/ada,\$(srcdir) on the output of the command given after my
signature is the starting point.

-- 
Laurent Guerby <guerby@acm.org>

cd gcc/gcc/ada
../../../install-2001-11-25-15-31-00/bin/gnatmake -M -I- -I. -I../../../gcc/gcc/ada ../../../gcc/gcc/ada/gnat1drv.adb

gnat1drv.o : ../../../gcc/gcc/ada/alloc.ads ../../../gcc/gcc/ada/atree.ads \
 ../../../gcc/gcc/ada/back_end.ads ../../../gcc/gcc/ada/casing.ads \
 ../../../gcc/gcc/ada/comperr.ads ../../../gcc/gcc/ada/csets.ads \
 ../../../gcc/gcc/ada/debug.ads ../../../gcc/gcc/ada/einfo.ads \
 ../../../gcc/gcc/ada/elists.ads ../../../gcc/gcc/ada/errout.ads \
 ../../../gcc/gcc/ada/fname.ads ../../../gcc/gcc/ada/fname-uf.ads \
 ../../../gcc/gcc/ada/frontend.ads ../../../gcc/gcc/ada/get_targ.ads \
 ../../../gcc/gcc/ada/gnat1drv.ads ../../../gcc/gcc/ada/gnat1drv.adb \
 ../../../gcc/gcc/ada/gnatvsn.ads ../../../gcc/gcc/ada/hostparm.ads \
 ../../../gcc/gcc/ada/inline.ads ../../../gcc/gcc/ada/lib.ads \
 ../../../gcc/gcc/ada/lib-writ.ads ../../../gcc/gcc/ada/namet.ads \
 ../../../gcc/gcc/ada/nlists.ads ../../../gcc/gcc/ada/opt.ads \
 ../../../gcc/gcc/ada/osint.ads ../../../gcc/gcc/ada/output.ads \
 ../../../gcc/gcc/ada/repinfo.ads ../../../gcc/gcc/ada/restrict.ads \
 ../../../gcc/gcc/ada/rident.ads ../../../gcc/gcc/ada/sem.ads \
 ../../../gcc/gcc/ada/sem_ch13.ads ../../../gcc/gcc/ada/sem_warn.ads \
 ../../../gcc/gcc/ada/sinfo.ads ../../../gcc/gcc/ada/sinput.ads \
 ../../../gcc/gcc/ada/sinput-l.ads ../../../gcc/gcc/ada/snames.ads \
 ../../../gcc/gcc/ada/sprint.ads ../../../gcc/gcc/ada/stringt.ads \
 ../../../gcc/gcc/ada/table.ads ../../../gcc/gcc/ada/targparm.ads \
 ../../../gcc/gcc/ada/tree_gen.ads ../../../gcc/gcc/ada/treepr.ads \
 ../../../gcc/gcc/ada/ttypes.ads ../../../gcc/gcc/ada/types.ads \
 ../../../gcc/gcc/ada/uintp.ads ../../../gcc/gcc/ada/uname.ads \
 ../../../gcc/gcc/ada/urealp.ads ../../../gcc/gcc/ada/usage.ads
atree.o : ../../../gcc/gcc/ada/alloc.ads ../../../gcc/gcc/ada/atree.ads \
 ../../../gcc/gcc/ada/atree.adb ../../../gcc/gcc/ada/casing.ads \
 ../../../gcc/gcc/ada/debug.ads ../../../gcc/gcc/ada/einfo.ads \
 ../../../gcc/gcc/ada/elists.ads ../../../gcc/gcc/ada/hostparm.ads \
 ../../../gcc/gcc/ada/nlists.ads ../../../gcc/gcc/ada/opt.ads \
 ../../../gcc/gcc/ada/output.ads ../../../gcc/gcc/ada/sinfo.ads \
 ../../../gcc/gcc/ada/sinput.ads ../../../gcc/gcc/ada/snames.ads \
 ../../../gcc/gcc/ada/table.ads ../../../gcc/gcc/ada/table.adb \
 ../../../gcc/gcc/ada/tree_io.ads ../../../gcc/gcc/ada/types.ads \
 ../../../gcc/gcc/ada/uintp.ads ../../../gcc/gcc/ada/urealp.ads

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