Rethink USE_ALIGNED_ACCESS macro in kvrocks code

[mapleFU]

Search before asking

• I had searched in the issues and found no similar issues.

Motivation

Redis uses USE_ALIGNED_ACCESS and check memory aligned in it's code:

1. For archs like ARM, memory access should be "aligned".
2. For arch like x86, it can use some code to do optimizations

This code leaves lots of ad-hoc optimizations in kvrocks. I think we need to check our compiler supports, does this really provides any optimizations

Solution

1. Checks USE_ALIGNED_ACCESS in code with compiler versions
2. Remove them if no really optimizations

Are you willing to submit a PR?

• I'm willing to submit a PR!