RFR: 8283447: Remove unused LIR_Assembler::_bs

[Thomas Schatzl]

Hi,

  can I have reviews for this trivial removal of the unused `LIR_Assembler::_bs ` member?

Test: gha, local compilation

Thanks,
  Thomas

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Commit messages:
 - Remove unused member

Changes: https://git.openjdk.java.net/jdk/pull/7887/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=7887&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8283447
  Stats: 6 lines in 2 files changed: 0 ins; 4 del; 2 mod
  Patch: https://git.openjdk.java.net/jdk/pull/7887.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/7887/head:pull/7887

PR: https://git.openjdk.java.net/jdk/pull/7887