Add "nonstring" attribute to hostmot2.h: rtapi_u8 board_name[8]; // ascii string, but not NULL terminated!

[smoe]

hal/drivers/mesa-hostmot2/llio_info.c:173:31: warning: initializer-string for array of ‘char’ truncates NUL terminator but destination lacks ‘nonstring’ attribute (9 chars into 8 available) [-Wunterminated-string-initialization]
  173 |                 .board_name = "MESA7C80",
      |                               ^~~~~~~~~~
hal/drivers/mesa-hostmot2/llio_info.c:184:31: warning: initializer-string for array of ‘char’ truncates NUL terminator but destination lacks ‘nonstring’ attribute (9 chars into 8 available) [-Wunterminated-string-initialization]
  184 |                 .board_name = "MESA7C81",
      |                               ^~~~~~~~~~
hal/drivers/mesa-hostmot2/llio_info.c:195:31: warning: initializer-string for array of ‘char’ truncates NUL terminator but destination lacks ‘nonstring’ attribute (9 chars into 8 available) [-Wunterminated-string-initialization]
  195 |                 .board_name = "MESA7I90",
      |                               ^~~~~~~~~~
hal/drivers/mesa-hostmot2/llio_info.c:206:31: warning: initializer-string for array of ‘char’ truncates NUL terminator but destination lacks ‘nonstring’ attribute (9 chars into 8 available) [-Wunterminated-string-initialization]
  206 |                 .board_name = "MESA7I43"

and indeed

hal/drivers/mesa-hostmot2/hostmot2.h:    rtapi_u8 board_name[8];  // ascii string, but not NULL terminated!

I suggest to follow the advice and add the https://gcc.gnu.org/onlinedocs/gcc/Common-Variable-Attributes.html#nonstring .