RFR: 8293214: Add support for Linux/LoongArch64 [v4]

[Ao Qi]

> LoongArch is a new RISC ISA. This issue proposes adding support for Linux/LoongArch64. Upstream WebKit for LoongArch64 support is not ready, but the OpenJFX part is simple and ready. When the LoongArch64 supported Webkit is updated to OpenJFX, it is supposed to work.
> 
> Testing:
> - [x] base, controls, fxml, graphics and web tests, {Release,Debug}, {with WebKit,without Webkit} on Linux/x64
> - [x] base, controls, fxml, graphics and web tests, {Release,Debug}, {with WebKit,without Webkit} on Linux/aarch64
> - [x] base, controls, fxml and graphics tests, {Release,Debug}, without WebKit on Linux/loongarch64

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

  disable msse2 by default, use IS_LOONGARCH64 and IS_AARCH64

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

Changes:
  - all: https://git.openjdk.org/jfx/pull/888/files
  - new: https://git.openjdk.org/jfx/pull/888/files/b225c59a..29e4b883

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jfx&pr=888&range=03
 - incr: https://webrevs.openjdk.org/?repo=jfx&pr=888&range=02-03

  Stats: 4 lines in 4 files changed: 0 ins; 0 del; 4 mod
  Patch: https://git.openjdk.org/jfx/pull/888.diff
  Fetch: git fetch https://git.openjdk.org/jfx pull/888/head:pull/888

PR: https://git.openjdk.org/jfx/pull/888