RFR: 8295417: Pass $AR to binutils cross-build

[Aleksey Shipilev]

While adapting my CI to build hsdis automatically, I realized that sometimes we miss the proper $AR for binutils cross-build. Configure would then fail like:


$ CXX=aarch64-linux-gnu-g++ CC=aarch64-linux-gnu-gcc sh ./configure --with-debug-level=fastdebug --openjdk-target=aarch64-linux-gnu --with-sysroot=/chroots/arm64 --with-boot-jdk=/home/shade/Install/jdk19u-ea --with-hsdis=binutils --with-binutils-src=binutils-2.38
...

-------------

Commit messages:
 - Fix

Changes: https://git.openjdk.org/jdk/pull/10729/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=10729&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8295417
  Stats: 2 lines in 1 file changed: 0 ins; 0 del; 2 mod
  Patch: https://git.openjdk.org/jdk/pull/10729.diff
  Fetch: git fetch https://git.openjdk.org/jdk pull/10729/head:pull/10729

PR: https://git.openjdk.org/jdk/pull/10729