lit: Show all output with --show-all, even in combination with --succinct

I missed an earlier exit for the --succinct case when I introduced the
-a option.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@252698 91177308-0d34-0410-b5e6-96231b3b80d8

utils/lit/lit/main.py

@@ -43,6 +43,7 @@ class TestingProgressDisplay(object):
                                     test.getFullName())
 
         shouldShow = test.result.code.isFailure or \
+            self.opts.showAllOutput or \
             (not self.opts.quiet and not self.opts.succinct)
         if not shouldShow:
             return