crypto/elliptic: gofmt

Change-Id: Ia4b49736d3b33cddf58905c6b19febbca45b2ad2
Reviewed-on: https://go-review.googlesource.com/64270Reviewed-by: Daniel Martí <mvdan@mvdan.cc>
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>

src/crypto/elliptic/p256_amd64.go

@@ -280,7 +280,7 @@ func uint64IsZero(x uint64) int {
 	x &= x >> 4
 	x &= x >> 2
 	x &= x >> 1
-	return int(x&1)
+	return int(x & 1)
 }
 
 // scalarIsZero returns 1 if scalar represents the zero value, and zero