RFR: 8256182: Update qemu-debootstrap cross-compilation recipe [v2]

[Aleksey Shipilev]

> Update the docs with the (f)actual recipe used in JDK-8256127.

Aleksey Shipilev has updated the pull request incrementally with one additional commit since the last revision:

  Remove newline before code block

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Changes:
  - all: https://git.openjdk.java.net/jdk/pull/1160/files
  - new: https://git.openjdk.java.net/jdk/pull/1160/files/ac27b8e3..187b2962

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=1160&range=01
 - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=1160&range=00-01

  Stats: 1 line in 1 file changed: 0 ins; 1 del; 0 mod
  Patch: https://git.openjdk.java.net/jdk/pull/1160.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/1160/head:pull/1160

PR: https://git.openjdk.java.net/jdk/pull/1160