Move bounded drawing calculation from interfaces into the only call site

[therealprof]

Hi! Thank you for helping out with SSD1306 development!

Please:

• Check that you've added documentation to any new methods
• Rebase from master if you're not already up to date
• Add or modify an example if there are changes to the public API
• Add a CHANGELOG.md entry in the Unreleased section under the appropriate heading (Added, Fixed, Changed, etc)
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PR description

Remove some code duplication in bounded box drawing by moving the bounding box calculation from the interface specific send_bounded_data into the only call site and reuse the regular send_data function.

[jamwaffles]

Hmm, weird that we didn't do this previously. Tested on hardware and looks good to me. Isn't this a breaking change though? Probably nobody is using send_bounded_data, but it's public. Can you add a breaking changelog entry saying it's been moved private or something?

[jamwaffles]

Oops wrong button

[therealprof]

It's a bit weird that this is a world-public interface. But I've added the entry as requested.

[therealprof]

NB: I've also tested the I2C version of this in one of my projects.

[jamwaffles]

It's a bit weird that this is a world-public interface. But I've added the entry as requested.

It should probably be private, no? I'm happy to make that breaking change. If someone really wants it, we can come up with a better solution down the road.

p.s. needs a rebase

[therealprof]

@jamwaffles Privatizing doesn't really work, already tried. It's too exposed but hey, maybe we're completely changing it anyways. 😅

[jamwaffles]

Looks good to me. Please merge when you want to.