Remove the obsolete and unused sqlite3.inTrans field.

FossilOrigin-Name: c3381cd4957013d46075996c3b865177c888d2a8

src/sqliteInt.h

@@ -748,7 +748,6 @@ typedef struct WhereLevel WhereLevel;
 struct Db {
   char *zName;         /* Name of this database */
   Btree *pBt;          /* The B*Tree structure for this database file */
-  u8 inTrans;          /* 0: not writable.  1: Transaction.  2: Checkpoint */
   u8 safety_level;     /* How aggressive at syncing data to disk */
   Schema *pSchema;     /* Pointer to database schema (possibly shared) */
 };