all: gofmt

Gofmt to update doc comments to the new formatting.

For golang/go#51082.

Change-Id: I076031b6613691eefbb0f21739366e3fd2011ec9
Reviewed-on: https://go-review.googlesource.com/c/crypto/+/399356
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gopher Robot <gobot@golang.org>
Auto-Submit: Russ Cox <rsc@golang.org>
Reviewed-by: Ian Lance Taylor <iant@google.com>

pbkdf2/pbkdf2.go

@@ -32,7 +32,7 @@ import (
 // can get a derived key for e.g. AES-256 (which needs a 32-byte key) by
 // doing:
 //
-// 	dk := pbkdf2.Key([]byte("some password"), salt, 4096, 32, sha1.New)
+//	dk := pbkdf2.Key([]byte("some password"), salt, 4096, 32, sha1.New)
 //
 // Remember to get a good random salt. At least 8 bytes is recommended by the
 // RFC.