Cleanup: fix compiler warnings.

source/blender/editors/sculpt_paint/paint_image_proj.c

@@ -1185,7 +1185,7 @@ static VertSeam *find_adjacent_seam(const ProjPaintState *ps, uint loop_index, u
 {
 	ListBase *vert_seams = &ps->vertSeams[vert_index];
 	VertSeam *seam = vert_seams->first;
-	VertSeam *adjacent;
+	VertSeam *adjacent = NULL;
 
 	while (seam->loop != loop_index) {
 		seam = seam->next;

source/blender/editors/space_image/image_ops.c

@@ -3011,7 +3011,7 @@ static void image_sample_rect_color_ubyte(
         const ImBuf *ibuf, const rcti *rect,
         uchar r_col[4], float r_col_linear[4])
 {
-	uint col_accum_ub[4];
+	uint col_accum_ub[4] = {0, 0, 0, 0};
 	zero_v4(r_col_linear);
 	int col_tot = 0;
 	int coord[2];