Fix clang-format complaint in rdb_datadic.h

Summary:
Fixes a few minor issues from Issue #881: Issue #809 still occurs for
reverse scans on forward cfs.

Squash with D10388394

Reviewed By: lth

Differential Revision: D10410065

fbshipit-source-id: 10df167

storage/rocksdb/rdb_datadic.h

@@ -265,7 +265,7 @@ class Rdb_key_def {
     else
       get_supremum_key(key, size);
 
-    /* Find out how many bytes of infimum are the same as m_index_number */
+    /* Find out how many bytes are the same as m_index_number */
     uchar unmodified_key[INDEX_NUMBER_SIZE];
     rdb_netbuf_store_index(unmodified_key, m_index_number);
     int i;
@@ -276,7 +276,6 @@ class Rdb_key_def {
     return i;
   }
 
-
   /* Make a key that is right after the given key. */
   static int successor(uchar *const packed_tuple, const uint &len);