mem-cache: Avoid hiding a virtual method in the dictionary compressor.

The non-virtual version is later used in overrides of the virtual
version whcih takes more arguments.

Change-Id: I102d1185c7a616337c2a0429daa998706189292f
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/23127
Reviewed-by: Daniel Carvalho <odanrc@yahoo.com.br>
Maintainer: Gabe Black <gabeblack@google.com>
Tested-by: kokoro <noreply+kokoro@google.com>

src/mem/cache/compressors/dictionary_compressor.hh

@@ -230,6 +230,8 @@ class DictionaryCompressor : public BaseDictionaryCompressor
     std::unique_ptr<BaseCacheCompressor::CompressionData> compress(
         const uint64_t* data);
 
+    using BaseDictionaryCompressor::compress;
+
     /**
      * Decompress data.
      *