Rename StaticXXBuffer to XXBuffer

[Dirbaio]

Following up on conversations from Matrix.

In 99.9% of the cases HALs should use the StaticXXBuffer traits. However, historically, many HAL implementors have gotten it wrong. Reasons:

• The difference between them is not easy to understand.
• The non-static traits look like the "default" choice due to the simpler name
• The non-static traits look like a better choice due to the better ergonomics of use

Their original purpose was to allow using (unsafely) non-'static buffers with DMA functions.
However, the newer StaticXXBuffer make this possible. They don't have a : 'static bound, but are implemented for 'static buffers only. This allows users to (unsafely) "escape" the requirement by unsafe impling StaticXXBuffer for their types.

Therefore IMO having two sets of traits isn't worth the confusion it adds.

Proposal:

• Remove ReadBuffer, WriteBuffer
• Rename StaticReadBuffer, StaticWriteBuffer to ReadBuffer, WriteBuffer

This is a breaking change of course.

[thalesfragoso]

Just passing by to say that I agree with this reasoning.