Align memory for SDC read on ChibiOS

[networkfusion]

Description

There were sporatic failures with firmware releases on STM32F7 series related to the ability to read the content of files. This is a speculative fix that addresses the immediate issue, although might need applying to MMC and also write functions.

It also addresses:

• A Fix for for Drive Indexes (that should only be a single char).
• Some comments (spelling) and code formatting.

Motivation and Context

Issues with reading from SD cards.

How Has This Been Tested?

Locally on an ORGPAL_THREE (though had to turn USB MSD OFF for the interpreter not to continually crash). Note: build dir must be cleared!

Screenshots

Types of changes

• Improvement (non-breaking change that improves a feature, code or algorithm)
• Bug fix (non-breaking change which fixes an issue with code or algorithm)
• New feature (non-breaking change which adds functionality to code)
• Breaking change (fix or feature that would cause existing functionality to change)
• Config and build (change in the configuration and build system, has no impact on code or features)
• Dev Containers (changes related with Dev Containers, has no impact on code or features)
• Dependencies (update dependencies and changes associated, has no impact on code or features)
• Documentation (changes or updates in the documentation, has no impact on code or features)

Checklist

• My code follows the code style of this project (only if there are changes in source code).
• My changes require an update to the documentation (there are changes that require the docs website to be updated).
• I have updated the documentation accordingly (the changes require an update on the docs in this repo).
• I have read the CONTRIBUTING document.
• I have tested everything locally and all new and existing tests passed (only if there are changes in source code).