netcdf Merge Request #1: Use size_t for array index (merged)

Getting the following warning:

__netcdf__.cc: In function ‘octave_value_list Fnetcdf_getAtt(const octave_value_list&, int)’:
__netcdf__.cc:1617:29: warning: comparison of integer expressions of different signedness: ‘int’ and ‘size_t’ {aka ‘long unsigned int’} [-Wsign-compare]
 1617 |            for (int vi=0; vi<len;vi++) {                                        \
      |                           ~~^~~~
__netcdf__.cc:1626:7: note: in expansion of macro ‘OV_NETCDF_GETVLEN_ATT_CASE’

[lostbard]

thanks for the patch - i merged it.
I see a few other warnings unrelated to this, that I will take a look at