CPack/Archive: Show filename causing same-file-different-content

When there are two files with the same name but different content, an
error is shown, but the error does not include the filename which caused
it. This adds the filename to the error.

Source/CPack/cmCPackArchiveGenerator.cxx

@@ -361,7 +361,8 @@ int cmCPackArchiveGenerator::addOneComponentToArchive(
     } else if (status == DeduplicateStatus::Error) {
       cmCPackLogger(cmCPackLog::LOG_ERROR,
                     "ERROR The data in files with the "
-                    "same filename is different.");
+                    "same filename is different: "
+                      << rp << std::endl);
       return 0;
     } else {
       cmCPackLogger(cmCPackLog::LOG_DEBUG,

Tests/RunCMake/CPack/tests/DUPLICATE_FILE/conflict_file-stderr.txt

@@ -1 +1 @@
-CPack Error: ERROR The data in files with the same filename is different.*
+CPack Error: ERROR The data in files with the same filename is different: files/1\.txt

Tests/RunCMake/CPack/tests/DUPLICATE_FILE/conflict_symlink-stderr.txt

@@ -1 +1 @@
-CPack Error: ERROR The data in files with the same filename is different.*
+CPack Error: ERROR The data in files with the same filename is different: files/symlink2