disk: replace into_iter() with equivalent iter()
disk: replace into_iter() with equivalent iter()

Fixes clippy warning:

  warning: this .into_iter() call is equivalent to .iter() and will not
  move the slice

BUG=None
TEST=bin/clippy

Change-Id: I5361495f02609dd5e5313b7bc792e663841212ad
Signed-off-by: Daniel Verkamp <72bc170b46ec491f7bdd4359a1c0bfed274de40c@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/crosvm/+/1896091
Reviewed-by: Zach Reizner <3374927928a53d04457674c546bd4de57c2044ec@chromium.org>
Tested-by: kokoro <2ac7b1f3fa578934c95181d4272be0d3bca00121@google.com>

google/crosvm,google/crosvm,google/crosvm,google/crosvm