Patch fixing a warning in AVR build

[kr . git]

Hello,

I would like to submit a patch that removes unused variable and fixes a 
warning while building NuttX for AVR DA chip with tickless enabled. This 
warning was introduced by commit e5db83d7dbb0 which removes call to 
function using that variable. Also updated is comment describing the 
changed code. (The change was tested by comparing built binary before 
and after the patch - they are identical - and I also ran the code on 
hardware.)

The patch is available in a git repository nuttx.git at git.kerogit.eu 
accessible through HTTP/S. (Trying to prevent bot traffic by not posting 
the URL in machine-readable form.) The relevant branch is called 
avrdx_fix_tickless.

As previously, I would like to ask someone with GitHub account to change 
this into a pull request.

Thanks.