Vendor go.etcd.io/bbolt @ v1.3.1-etcd.8

Signed-off-by: John Howard <jhoward@microsoft.com>

This is the maintained version of boltdb, which includes the Windows-specific fix
detailed in https://github.com/etcd-io/bbolt/pull/122

vendor/go.etcd.io/bbolt/bolt_mipsx.go

@@ -0,0 +1,12 @@
+// +build mips mipsle
+
+package bbolt
+
+// maxMapSize represents the largest mmap size supported by Bolt.
+const maxMapSize = 0x40000000 // 1GB
+
+// maxAllocSize is the size used when creating array pointers.
+const maxAllocSize = 0xFFFFFFF
+
+// Are unaligned load/stores broken on this arch?
+var brokenUnaligned = false