[RFA/testsuite/ada] Do not abort prematurely the test upon build failure

[Michael Elizabeth Chastain]

Joel> lib/ada.exp (gdb_compile_ada): Emit UNSUPPORTED if we failed
Joel> to build the application. Remove the message printed when in
Joel> verbose mode, redundant with the UNSUPPORTED message above.

ac> Michael, shouldn't this be "UNTESTED"?  The feature works, we just 
ac> failed to test it.

I favor UNSUPPORTED for this, because the Ada compiler failed to run
on that platform.  Thus Ada is unsupported on that specific machine.
It's a bit of an assumption to go from that specific machine to all
machines of that platform, though.

I won't object if someone gives a result of UNTESTED in a situation
like this, though.

Michael C