Jeff Epler 9bd2a61d8b supervisor: Always allocate at least a 1x1 terminal
Otherwise, out of range writes would occur in tilegrid_set_tile, causing a safe mode reset.
```
Hardware watchpoint 6: -location *stack_alloc->ptr

Old value = 24652061
New value = 24641565
0x000444f2 in common_hal_displayio_tilegrid_set_tile (self=0x200002c8 <supervisor_terminal_text_grid>, x=1, y=1, tile_index=0 '\000')
    at ../../shared-module/displayio/TileGrid.c:236
236	    if (!self->partial_change) {
(gdb)
```
2020-09-01 10:55:45 -05:00
..
2018-08-07 14:58:57 -07:00
2020-07-06 19:16:25 +01:00
2020-07-06 19:16:25 +01:00
2020-01-28 17:11:25 -05:00
2020-08-19 16:47:40 -05:00