Haiku: several smaller fixes to build and run rust on Haiku

[nielx]

This PR combines three small patches that help Rust build and run on the Haiku platform. These patches do not intend to impact other platforms.

[rust-highfive]

r? @pnkfelix

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[rust-highfive]

The job x86_64-gnu-llvm-3.9 of 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.

[00:05:22] travis_fold:start:tidy
travis_time:start:tidy
tidy check
[00:05:22] tidy error: /checkout/src/librustc_target/spec/x86_64_unknown_haiku.rs:20: trailing whitespace
[00:05:24] some tidy checks failed
[00:05:24] 
[00:05:24] 
[00:05:24] command did not execute successfully: "/checkout/obj/build/x86_64-unknown-linux-gnu/stage0-tools-bin/tidy" "/checkout/src" "/checkout/obj/build/x86_64-unknown-linux-gnu/stage0/bin/cargo" "--no-vendor" "--quiet"
[00:05:24] 
[00:05:24] 
[00:05:24] failed to run: /checkout/obj/build/bootstrap/debug/bootstrap test src/tools/tidy
[00:05:24] Build completed unsuccessfully in 0:01:57
[00:05:24] Build completed unsuccessfully in 0:01:57
[00:05:24] make: *** [tidy] Error 1
[00:05:24] Makefile:79: recipe for target 'tidy' failed

The command "stamp sh -x -c "$RUN_SCRIPT"" exited with 2.
travis_time:start:19e6de5d
$ date && (curl -fs --head https://google.com | grep ^Date: | sed 's/Date: //g' || true)
---
travis_time:end:0be45cc8:start=1529852981047450369,finish=1529852981054116015,duration=6665646
travis_fold:end:after_failure.3
travis_fold:start:after_failure.4
travis_time:start:0889cc8a
$ head -30 ./obj/build/x86_64-unknown-linux-gnu/native/asan/build/lib/asan/clang_rt.asan-dynamic-i386.vers || true
head: cannot open ‘./obj/build/x86_64-unknown-linux-gnu/native/asan/build/lib/asan/clang_rt.asan-dynamic-i386.vers’ for reading: No such file or directory
travis_fold:end:after_failure.4
travis_fold:start:after_failure.5
travis_time:start:20bf4fee
$ 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)

[stokhos]

ping from triage, @pnkfelix ,will you have time to review this PR in near future?

[stokhos]

ping from triage @pnkfelix @rust-lang/compiler , will you have time to review this PR in near future?

[nagisa]

@bors r+

Seems good to me.

[bors]

📌 Commit bbe45ce has been approved by nagisa

[bors]

⌛ Testing commit bbe45ce with merge e06c875...

[bors]

☀️ Test successful - status-appveyor, status-travis
Approved by: nagisa
Pushing e06c875 to master...