fix(vg_lite): fix LV_RADIUS_CIRCLE not round

[FASTSHIFT]

Description of the feature or fix

Dividing by 2 for odd integers results in loss of precision.

void test_demo()
{
    lv_obj_t* main_obj = lv_obj_create(lv_scr_act());
    lv_obj_set_style_pad_all(main_obj, 0, 0);
    lv_obj_set_style_radius(main_obj, LV_RADIUS_CIRCLE, 0);
    lv_obj_set_style_bg_color(main_obj, lv_palette_main(LV_PALETTE_BLUE), 0);
    lv_obj_set_size(main_obj, 279, 279);
}

Before:

After:

Notes

• Update the Documentation if needed.
• Add Examples if relevant.
• Add Tests if applicable.
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