RFR: 8270517: Add Zero support for LoongArch [v2]

[Ao Qi]

> LoongArch is a new RISC ISA. This issue proposes adding Zero support for LoongArch. Only 64-bit support is proposed at present.
> 
> linux-loongarch64-zero-{release, fastdebug} build tested:
> 
> $ ./build/linux-loongarch64-zero-fastdebug/jdk/bin/java -version
> openjdk version "18-internal" 2022-03-15
> OpenJDK Runtime Environment (fastdebug build 18-internal+0-adhoc.aoqi.jdk)
> OpenJDK 64-Bit Zero VM (fastdebug build 18-internal+0-adhoc.aoqi.jdk, interpreted mode)

Ao Qi has updated the pull request incrementally with one additional commit since the last revision:

  removed redundant whitespaces

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

Changes:
  - all: https://git.openjdk.java.net/jdk/pull/4787/files
  - new: https://git.openjdk.java.net/jdk/pull/4787/files/bd626159..5dbfe543

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=4787&range=01
 - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=4787&range=00-01

  Stats: 1 line in 1 file changed: 0 ins; 0 del; 1 mod
  Patch: https://git.openjdk.java.net/jdk/pull/4787.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/4787/head:pull/4787

PR: https://git.openjdk.java.net/jdk/pull/4787