Do random number generation all at once.

Splitting it into chunks is handled in the go mx syscall now.

Change-Id: I439faaca20b7569b0803fb142dcaaa2a687a9045
diff --git a/tcpip/network/hash/hash.go b/tcpip/network/hash/hash.go
index 20fb76d..a1f33d6 100644
--- a/tcpip/network/hash/hash.go
+++ b/tcpip/network/hash/hash.go
@@ -18,16 +18,8 @@
 // RandN32 generates a slice of n cryptographic random 32-bit numbers.
 func RandN32(n int) []uint32 {
 	b := make([]byte, 4*n)
-	// Read in 256-byte increments because the Fuchsia crypto library doesn't support large
-	// byte arrays.
-	for i := 0; i < 4*n; i += 256 {
-		end := i + 256
-		if end > len(b) {
-			end = len(b)
-		}
-		if _, err := rand.Read(b[i:end]); err != nil {
-			panic(fmt.Sprintf("unable to get random numbers: %v", err))
-		}
+	if _, err := rand.Read(b); err != nil {
+		panic(fmt.Sprintf("unable to get random numbers: %v", err))
 	}
 	r := make([]uint32, n)
 	for i := range r {