RFR: 8269672: C1: Remove unaligned move on all architectures

[Yi Yang]

This is a follow up PR for #3917, no functional change.

As @TheRealMDoerr said 

The "unaligned" parameter is unused on all platforms, now. Note that PPC64 and s390 support unaligned accesses, too. I believe it was used by SPARC which has been removed.

Thanks！

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

Commit messages:
 - remove unaligned

Changes: https://git.openjdk.java.net/jdk/pull/4662/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=4662&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8269672
  Stats: 66 lines in 19 files changed: 0 ins; 27 del; 39 mod
  Patch: https://git.openjdk.java.net/jdk/pull/4662.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/4662/head:pull/4662

PR: https://git.openjdk.java.net/jdk/pull/4662