Fix repaintable stack calculation (#5821)
Fix repaintable stack calculation (#5821)

* Fix repaintable stack calculation

Fixes #5794 as found by @mattbradford83

* Overwrite last word of stack as well

Under-by-one error would not reset the absolute end of the stack, adjust
comparison to fix.

esp8266/Arduino,esp8266/Arduino,sticilface/Arduino,Lan-Hekary/Arduino,esp8266/Arduino,esp8266/Arduino,Lan-Hekary/Arduino,Lan-Hekary/Arduino,esp8266/Arduino,sticilface/Arduino,sticilface/Arduino,Lan-Hekary/Arduino,sticilface/Arduino,Lan-Hekary/Arduino,sticilface/Arduino