Rename the Db.zName field to Db.zDbSName to make it more descriptive and to
distinguish it from all of the other "zName" variables scattered throughout
the code.

FossilOrigin-Name: 92a22f01343a898455fd61c3b8e7d7c954f5b569
diff --git a/src/sqliteInt.h b/src/sqliteInt.h
index 0ce56ce..17f3efc 100644
--- a/src/sqliteInt.h
+++ b/src/sqliteInt.h
@@ -1097,7 +1097,7 @@
 ** databases may be attached.
 */
 struct Db {
-  char *zName;         /* Name of this database */
+  char *zDbSName;      /* Name of this database. (schema name, not filename) */
   Btree *pBt;          /* The B*Tree structure for this database file */
   u8 safety_level;     /* How aggressive at syncing data to disk */
   u8 bSyncSet;         /* True if "PRAGMA synchronous=N" has been run */