If the sector size is unspecified (initially 0) then set it to 512, not to 32.

FossilOrigin-Name: 8861b5c16031ad570ffbe17b3ec8163b136a7f63
diff --git a/src/pager.c b/src/pager.c
index 85a99a1..f2099c4 100644
--- a/src/pager.c
+++ b/src/pager.c
@@ -1794,7 +1794,7 @@
     pPager->sectorSize = sqlite3OsSectorSize(pPager->fd);
   }
   if( pPager->sectorSize<32 ){
-    pPager->sectorSize = 32;
+    pPager->sectorSize = 512;
   }
   if( pPager->sectorSize>MAX_SECTOR_SIZE ){
     assert( MAX_SECTOR_SIZE>=512 );