Remove unused rename code

The code that attempts to rename the generated zip file is a no-op
since the new and old names are the same.

Also fixed a couple of typos.

Test: adb shell /data/nativetest64/dumpstate_test/dumpstate_test
Change-Id: I5054e141a8248add15d7ad5a9ef7c40a01c939cd
diff --git a/cmds/dumpstate/dumpstate.h b/cmds/dumpstate/dumpstate.h
index 5e7f71d..35cbdb1 100644
--- a/cmds/dumpstate/dumpstate.h
+++ b/cmds/dumpstate/dumpstate.h
@@ -261,7 +261,7 @@
                                         std::chrono::milliseconds timeout);
 
     /*
-     * Adds a text entry entry to the existing zip file.
+     * Adds a text entry to the existing zip file.
      */
     bool AddTextZipEntry(const std::string& entry_name, const std::string& content);