Fix compiler warnings on Windows.

FossilOrigin-Name: 512b8e40c4ce2066d230b5f007bd704dc3577e21c55131ef07d90bf2fcf91b40
diff --git a/src/sqliteInt.h b/src/sqliteInt.h
index 35074ee..757cfcb 100644
--- a/src/sqliteInt.h
+++ b/src/sqliteInt.h
@@ -1365,9 +1365,9 @@
     int newTnum;                /* Rootpage of table being initialized */
     u8 iDb;                     /* Which db file is being initialized */
     u8 busy;                    /* TRUE if currently initializing */
-    u8 orphanTrigger : 1;       /* Last statement is orphaned TEMP trigger */
-    u8 imposterTable : 1;       /* Building an imposter table */
-    u8 reopenMemdb : 1;         /* ATTACH is really a reopen using MemDB */
+    unsigned orphanTrigger : 1; /* Last statement is orphaned TEMP trigger */
+    unsigned imposterTable : 1; /* Building an imposter table */
+    unsigned reopenMemdb : 1;   /* ATTACH is really a reopen using MemDB */
   } init;
   int nVdbeActive;              /* Number of VDBEs currently running */
   int nVdbeRead;                /* Number of active VDBEs that read or write */