RFR: 8363943: ARM32: Represent Registers as values [v2]

[Ivan]

> Migrate away from pointer-based representation of Register values.
> 
> It improves compile-time checking by forbidding implicit conversions between integrals and pointers.
> 
> [JDK-8363943](https://bugs.openjdk.org/browse/JDK-8363943)

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

  Proposed review changes were applied

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/26525/files
  - new: https://git.openjdk.org/jdk/pull/26525/files/f75b381f..962b01b6

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=26525&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=26525&range=00-01

  Stats: 46 lines in 2 files changed: 0 ins; 4 del; 42 mod
  Patch: https://git.openjdk.org/jdk/pull/26525.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/26525/head:pull/26525

PR: https://git.openjdk.org/jdk/pull/26525