Bump AWS SDK

Fixes https://github.com/docker/distribution/issues/3097

Signed-off-by: Yong Wen Chua <lawliet89@users.noreply.github.com>

vendor/github.com/aws/aws-sdk-go/internal/sdkmath/floor.go

@@ -0,0 +1,15 @@
+// +build go1.10
+
+package sdkmath
+
+import "math"
+
+// Round returns the nearest integer, rounding half away from zero.
+//
+// Special cases are:
+//	Round(±0) = ±0
+//	Round(±Inf) = ±Inf
+//	Round(NaN) = NaN
+func Round(x float64) float64 {
+	return math.Round(x)
+}

vendor/github.com/aws/aws-sdk-go/internal/sdkmath/floor_go1.9.go

@@ -0,0 +1,56 @@
+// +build !go1.10
+
+package sdkmath
+
+import "math"
+
+// Copied from the Go standard library's (Go 1.12) math/floor.go for use in
+// Go version prior to Go 1.10.
+const (
+	uvone    = 0x3FF0000000000000
+	mask     = 0x7FF
+	shift    = 64 - 11 - 1
+	bias     = 1023
+	signMask = 1 << 63
+	fracMask = 1<<shift - 1
+)
+
+// Round returns the nearest integer, rounding half away from zero.
+//
+// Special cases are:
+//	Round(±0) = ±0
+//	Round(±Inf) = ±Inf
+//	Round(NaN) = NaN
+//
+// Copied from the Go standard library's (Go 1.12) math/floor.go for use in
+// Go version prior to Go 1.10.
+func Round(x float64) float64 {
+	// Round is a faster implementation of:
+	//
+	// func Round(x float64) float64 {
+	//   t := Trunc(x)
+	//   if Abs(x-t) >= 0.5 {
+	//     return t + Copysign(1, x)
+	//   }
+	//   return t
+	// }
+	bits := math.Float64bits(x)
+	e := uint(bits>>shift) & mask
+	if e < bias {
+		// Round abs(x) < 1 including denormals.
+		bits &= signMask // +-0
+		if e == bias-1 {
+			bits |= uvone // +-1
+		}
+	} else if e < bias+shift {
+		// Round any abs(x) >= 1 containing a fractional component [0,1).
+		//
+		// Numbers with larger exponents are returned unchanged since they
+		// must be either an integer, infinity, or NaN.
+		const half = 1 << (shift - 1)
+		e -= bias
+		bits += half >> e
+		bits &^= fracMask >> e
+	}
+	return math.Float64frombits(bits)
+}