$ sudo apt-get remove gdb-avr 

Uninstall gdb-avr including dependent package

If you would like to remove gdb-avr and it's dependent packages which are no longer needed from Ubuntu,

$ sudo apt-get remove --auto-remove gdb-avr 

Use Purging gdb-avr

If you use with purge options to gdb-avr package all the configuration and dependent packages will be removed.

$ sudo apt-get purge gdb-avr 

If you use purge options along with auto remove, will be removed everything regarding the package, It's really useful when you want to reinstall again.

$ sudo apt-get purge --auto-remove gdb-avr 

See Also,