tests: make fp-test less chatty when running from test suite

tests: make fp-test less chatty when running from test suite

As we like to run tests under CI with V=1 flags the softfloat tests
can add up to a fair amount of extra log lines. With an update to the
testfloat library we can now call fp-test with the -q flag and reduce
the output to a terse one line per function tested.

  make check-softfloat V=1 | wc -l
  759

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230228190653.1602033-5-alex.bennee@linaro.org>