RFR: 8319690: [AArch64] C2 compilation hits offset_ok_for_immed: assert "c2 compiler bug"

[Emanuel Peter]

Taking this over from @fg1417, she seems to be "on leave" according to her GitHub account.

I'm taking her regression test (she improved the reproducer that I had originally reported the bug with).

It is ok to just remove the assert, because the address is "sanitized" after the assert, i.e. we use a `lea` instruction to compute the address.

But I'm simply removing the assert, as suggested in the comments of the previous [PR](https://github.com/openjdk/jdk/pull/16991#issuecomment-1962307596).

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Commit messages:
 - remove the assert
 - 8319690

Changes: https://git.openjdk.org/jdk/pull/18103/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=18103&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8319690
  Stats: 176 lines in 2 files changed: 172 ins; 4 del; 0 mod
  Patch: https://git.openjdk.org/jdk/pull/18103.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/18103/head:pull/18103

PR: https://git.openjdk.org/jdk/pull/18103