stats: Correctly print new-style dist stat names
stats: Correctly print new-style dist stat names

The text stat printer didn't output fully qualified names for
new-style dist stats. Fix that.

Change-Id: I61bc7403fbd760bbbb0641e8e593781e6d03a4ed
Signed-off-by: Andreas Sandberg <c9f5686ee5bd561c93f9de79681eee75bfa7f36e@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/21162
Tested-by: kokoro <2ac7b1f3fa578934c95181d4272be0d3bca00121@google.com>
Reviewed-by: Bobby R. Bruce <b9dba908ffb6c6d8ffe449cc88b3709c13c485c2@ucdavis.edu>

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