core/vm, crypto/blake2b: add BLAKE2b compression func at 0x09

The precompile at 0x09 wraps the BLAKE2b F compression function:
https://tools.ietf.org/html/rfc7693#section-3.2

The precompile requires 6 inputs tightly encoded, taking exactly 213
bytes, as explained below.

- `rounds` - the number of rounds - 32-bit unsigned big-endian word
- `h` - the state vector - 8 unsigned 64-bit little-endian words
- `m` - the message block vector - 16 unsigned 64-bit little-endian words
- `t_0, t_1` - offset counters - 2 unsigned 64-bit little-endian words
- `f` - the final block indicator flag - 8-bit word

[4 bytes for rounds][64 bytes for h][128 bytes for m][8 bytes for t_0]
[8 bytes for t_1][1 byte for f]

The boolean `f` parameter is considered as `true` if set to `1`.
The boolean `f` parameter is considered as `false` if set to `0`.
All other values yield an invalid encoding of `f` error.

The precompile should compute the F function as specified in the RFC
(https://tools.ietf.org/html/rfc7693#section-3.2) and return the updated
state vector `h` with unchanged encoding (little-endian).

See EIP-152 for details.

eth/tracers/tracer.go

@@ -390,7 +390,7 @@ func New(code string) (*Tracer, error) {
 		return 1
 	})
 	tracer.vm.PushGlobalGoFunction("isPrecompiled", func(ctx *duktape.Context) int {
-		_, ok := vm.PrecompiledContractsByzantium[common.BytesToAddress(popSlice(ctx))]
+		_, ok := vm.PrecompiledContractsIstanbul[common.BytesToAddress(popSlice(ctx))]
 		ctx.PushBoolean(ok)
 		return 1
 	})