tests: better %check error logging

Don't run the testsuite twice now (with/without -v option), but
rather /bin/cat all the testsuite.log files when 'make check'
fails.

Version: 1.30-1

tar.spec

@@ -92,7 +92,16 @@ rm -f $RPM_BUILD_ROOT%{_mandir}/man8/rmt.8*
 %check
 %if %{with check}
 rm -f $RPM_BUILD_ROOT/test/testsuite
-make check || TESTSUITEFLAGS=-v make check
+make check || (
+    # get the error log
+    set +x
+    find -name testsuite.log | while read line; do
+        echo "=== $line ==="
+        cat "$line"
+        echo
+    done
+    false
+)
 %endif
 
 %clean