[AVR] Fixed USB_SendControl for buffer size > 64

[cmaglie]

This is the best implementation I've got so far, this add 52 bytes (of ~3900 total) to the empty sketch.

I have not tested with transfers > 64 bytes, @NicoHood may you give it a try?

related to #4317
/cc @facchinm

[ArduinoBot]

Build successful. Please test this code using one of the following:
http://downloads.arduino.cc/javaide/pull_requests/arduino-PR-4325-BUILD-458-linux32.tar.xz
http://downloads.arduino.cc/javaide/pull_requests/arduino-PR-4325-BUILD-458-linux64.tar.xz
http://downloads.arduino.cc/javaide/pull_requests/arduino-PR-4325-BUILD-458-windows.zip
http://downloads.arduino.cc/javaide/pull_requests/arduino-PR-4325-BUILD-458-macosx.zip

[NicoHood]

This was my fix:
NicoHood@71c88b6

You might want to check if my version gives the same overhead.

@facchinm rejected it cause of the overhead. That's why I added the Long function, because I need the 64 byte fix. From theory it should work, but I cannot test right now.

[cmaglie]

hi @NicoHood

I remember that @facchinm has discussed this one briefly with me, probably at the time I didn't understood the relevance of this patch, so sorry to take so long to make up our mind!

I checked your patch it seems to be the best until now:

patch	empty sketch size	delta
no patch	3916	0
NicoHood@71c88b6	3966	+50
cmaglie@de5a139	3968	+52

So, I'm going to use you patch at NicoHood@71c88b6

thanks!

[NicoHood]

You might want to rename the variables, the names are horrible tbh by myself. But yeah, thx for adding this!