Grbl Settings Mismatch between GrblHAL and Grbl_Esp32

[synman]

5b33828#comments

[synman]

@paukstelis thinking thru how best to address this. I'm so annoyed that GrblHAL and Grbl_ESP32 / FluidNC collided.

I'm also dreading having to separate out the error files based grbl flavor but I can't think of a better approach. The existing checks for Grbl_ESP32 and FluidNC will come in handy here once I commit to fixing this.