v.kriging: fix compilation warnings

[tmszi]

Fix compilation warnings:

utils_kriging.c: In function ‘crossvalidation’:
utils_kriging.c:716:32: warning: passing argument 3 of ‘submatrix’ from incompatible pointer type [-Wincompatible-pointer-types]
  716 |                                &xD->report);   // create submatrix using indices
      |                                ^~~~~~~~~~~
      |                                |
      |                                struct write **
utils_kriging.c:415:37: note: expected ‘struct write *’ but argument is of type ‘struct write **’
  415 |                       struct write *report)
      |                       ~~~~~~~~~~~~~~^~~~~~
utils_kriging.c: In function ‘compare_NN’:
utils_kriging.c:837:26: warning: initialization of ‘double *’ from incompatible pointer type ‘int *’ [-Wincompatible-pointer-types]
  837 |     double *list_value = list->value;
      |                          ^~~~
utils_kriging.c:838:30: warning: initialization of ‘double *’ from incompatible pointer type ‘int *’ [-Wincompatible-pointer-types]
  838 |     double *list_new_value = list_new->value;
      |                              ^~~~~~~~
utils_kriging.c: In function ‘make_subsamples’:
utils_kriging.c:862:28: warning: initialization of ‘struct write *’ from incompatible pointer type ‘struct write **’ [-Wincompatible-pointer-types]
  862 |     struct write *report = &xD->report;
      |                            ^
utils_raster.c: In function ‘open_layer’:
utils_raster.c:6:28: warning: initialization of ‘struct write *’ from incompatible pointer type ‘struct write **’ [-Wincompatible-pointer-types]
    6 |     struct write *report = &xD->report;
      |                            ^
utils_raster.c: In function ‘write2layer’:
utils_raster.c:37:28: warning: initialization of ‘struct write *’ from incompatible pointer type ‘struct write **’ [-Wincompatible-pointer-types]
   37 |     struct write *report = &xD->report;

line 100 print warning too:

utils_kriging.c: In function ‘LMS_variogram’:
utils_kriging.c:100:73: warning: format ‘%f’ expects a matching ‘double’ argument [-Wformat=]
  100 |             fprintf(report->fp, "gamma(h, vert) = %f * h + %f * vert + %f\n",
      |                                                                        ~^
      |                                                                         |
      |                                                                         double

line 94 and 100 look the same (fprintf() func has same string arg):

grass-addons/src/vector/v.kriging/utils_kriging.c

Lines 91 to 103 in 5633a4b

	if (report->name) {
	if (var_par->function == 5) {
	fprintf(report->fp, "Parameters of bivariate variogram:\n");
	fprintf(report->fp, "gamma(h, vert) = %f * h + %f * vert + %f\n",
	var_par->T->vals[0], var_par->T->vals[1],
	var_par->T->vals[2]);
	}
	else {
	fprintf(report->fp, "Parameters of univariate variogram:\n");
	fprintf(report->fp, "gamma(h, vert) = %f * h + %f * vert + %f\n",
	var_par->T->vals[0], var_par->T->vals[1]);
	}
	} // end if: report

Is there a difference between the number of bivariate and univariate variogram parameters?