Fix uint64 un-aligned atomic access

[cmaglie]

Should fix #87.

/cc @wjwieland @OBerghmans

[codecov]

Codecov Report

Merging #91 into master will decrease coverage by 0.04%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master      #91      +/-   ##
==========================================
- Coverage   47.98%   47.93%   -0.05%     
==========================================
  Files          92       92              
  Lines        4087     4087              
==========================================
- Hits         1961     1959       -2     
- Misses       1889     1891       +2     
  Partials      237      237

Impacted Files	Coverage Δ
common/formatter/output/libraries.go	81.08% <0%> (-5.41%)	⬇️

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[ArduinoBot]

✅ Build completed.

⬇️ Linux 64: http://downloads.arduino.cc/PR/arduino-cli/arduino-cli-25-PR91-linux64.tar.bz2

⬇️ Linux 32: http://downloads.arduino.cc/PR/arduino-cli/arduino-cli-25-PR91-linux32.tar.bz2

⬇️ Linux ARM: http://downloads.arduino.cc/PR/arduino-cli/arduino-cli-25-PR91-linuxarm.tar.bz2

⬇️ Windows: http://downloads.arduino.cc/PR/arduino-cli/arduino-cli-25-PR91-windows.zip

⬇️ OSX: http://downloads.arduino.cc/PR/arduino-cli/arduino-cli-25-PR91-osx.zip

ℹ️ To test this build:

1. Just replace arduino-cli binary with the provided one

[wjwieland]

I can confirm update-index for both core and lib on the linux 64 and linux ARM now work as expected. For some reason I get 404 - not found error when attempting to retrieve the Linux 32 tar.bz2 file from the above 'Build completed' download link, so have not yet tested on my 32 bit system.

Thanks again for the work on this!