Further simplifications to the SHM locking logic.  Remove the SQLITE_SHM_QUERY
option.  Unify the WRITE to READ and RECOVER to READ transitions.

FossilOrigin-Name: e9bfa6e4ce7d1edc6be8b9173ac3b6bfd180632a
diff --git a/src/sqlite.h.in b/src/sqlite.h.in
index f7d462f..2672690 100644
--- a/src/sqlite.h.in
+++ b/src/sqlite.h.in
@@ -879,10 +879,7 @@
 ** CAPI3REF: Flags for the xShmLock VFS method
 **
 ** These integer constants define the various locking states that
-** an sqlite3_shm object can be in.  The SQLITE_SHM_QUERY integer
-** is not a valid data - it is a constant pasted to the 
-** sqlite3_vfs.xShmLock() method for querying the current lock
-** state.
+** an sqlite3_shm object can be in.
 */
 #define SQLITE_SHM_UNLOCK       0
 #define SQLITE_SHM_READ         1
@@ -891,7 +888,6 @@
 #define SQLITE_SHM_PENDING      4
 #define SQLITE_SHM_CHECKPOINT   5
 #define SQLITE_SHM_RECOVER      6
-#define SQLITE_SHM_QUERY        (-1)
 
 /*
 ** CAPI3REF: Initialize The SQLite Library