FIX:使用cairo时round_radius丢失的问题

应该是当时忘记写了，圆角信息并没有成功写入

src/vgcanvas/vgcanvas_cairo.c

@@ -881,6 +881,7 @@ vgcanvas_t* vgcanvas_create(uint32_t w, uint32_t h, uint32_t stride, bitmap_form
   cairo->base.h = h;
   cairo->base.vt = &vt;
   cairo->base.ratio = 1;
+  cairo->base.stride = stride;
   cairo->base.format = format;
   cairo->base.buff = (uint32_t*)data;