[beta] Backport fixes to build-manifest

[pietroalbini]

Backports the following changes to beta:

• Fix build of the build-manifest tool #56703: Fix build of the build-manifest tool (partial, just added last commit)
• Add --pinentry-mode=loopback to deployment script #56783: Add --pinentry-mode=loopback to deployment script
• Fix gpg signing in manifest builder #56735: Fix gpg signing in manifest builder

r? @ghost
cc @Mark-Simulacrum @alexcrichton

[pietroalbini]

@bors r+ p=500

[bors]

📌 Commit 9b226dd has been approved by pietroalbini

[bors]

⌛ Testing commit 9b226dd with merge edc9874d1a30c933c0da34d56cb1347c75aa90e0...

[pietroalbini]

@bors retry

Yielding priority to stable.

[rust-highfive]

Your PR failed on Travis (raw log). Through arcane magic we have determined that the following fragments from the build log may contain information about the problem.

Click to expand the log.

Resolving deltas: 100% (7622/7622), done.
travis_time:end:0364e738:start=1545174584365190276,finish=1545174590238906135,duration=5873715859
$ cd rust-lang/rust
$ git checkout -qf edc9874d1a30c933c0da34d56cb1347c75aa90e0
fatal: reference is not a tree: edc9874d1a30c933c0da34d56cb1347c75aa90e0
The command "git checkout -qf edc9874d1a30c933c0da34d56cb1347c75aa90e0" failed and exited with 128 during .
Your build has been stopped.

I'm a bot! I can only do what humans tell me to, so if this was not helpful or you have suggestions for improvements, please ping or otherwise contact @TimNN. (Feature Requests)

[rust-highfive]

Your PR failed on Travis (raw log). Through arcane magic we have determined that the following fragments from the build log may contain information about the problem.

Click to expand the log.

travis_time:end:02e34808:start=1545170951487807110,finish=1545171015930601575,duration=64442794465
$ git checkout -qf FETCH_HEAD
travis_fold:end:git.checkout

Encrypted environment variables have been removed for security reasons.
See https://docs.travis-ci.com/user/pull-requests/#pull-requests-and-security-restrictions
$ export SCCACHE_BUCKET=rust-lang-ci-sccache2
$ export SCCACHE_REGION=us-west-1
Setting environment variables from .travis.yml
$ export IMAGE=mingw-check
---
travis_time:end:1f744e23:start=1545171959933930500,finish=1545171959940729635,duration=6799135
travis_fold:end:after_failure.3
travis_fold:start:after_failure.4
travis_time:start:18bedc19
$ ln -s . checkout && for CORE in obj/cores/core.*; do EXE=$(echo $CORE | sed 's|obj/cores/core\.[0-9]*\.!checkout!\(.*\)|\1|;y|!|/|'); if [ -f "$EXE" ]; then printf travis_fold":start:crashlog\n\033[31;1m%s\033[0m\n" "$CORE"; gdb --batch -q -c "$CORE" "$EXE" -iex 'set auto-load off' -iex 'dir src/' -iex 'set sysroot .' -ex bt -ex q; echo travis_fold":"end:crashlog; fi; done || true
travis_fold:end:after_failure.4
travis_fold:start:after_failure.5
travis_time:start:07d0a82a
travis_time:start:07d0a82a
$ cat ./obj/build/x86_64-unknown-linux-gnu/native/asan/build/lib/asan/clang_rt.asan-dynamic-i386.vers || true
cat: ./obj/build/x86_64-unknown-linux-gnu/native/asan/build/lib/asan/clang_rt.asan-dynamic-i386.vers: No such file or directory
travis_fold:end:after_failure.5
travis_fold:start:after_failure.6
travis_time:start:08566cc8
$ dmesg | grep -i kill

I'm a bot! I can only do what humans tell me to, so if this was not helpful or you have suggestions for improvements, please ping or otherwise contact @TimNN. (Feature Requests)

[bors]

⌛ Testing commit 9b226dd with merge a01b0bf...

[bors]

☀️ Test successful - status-appveyor, status-travis
Approved by: pietroalbini
Pushing a01b0bf to beta...