libaribcaption: remove unneeded strlen() check

var_InheritString() guarantees that, if the string returned is not NULL,
the string does not contain a NULL terminator as first character.

Checking for strlen() > 0 does the same as checking if the string
contains a NULL terminator as first character, because strlen() doesn't
count the NULL terminator. Thus, remove the unneeded check.

modules/codec/arib/libaribcaption.c

@@ -416,7 +416,7 @@ static int Open(vlc_object_t *p_this)
     aribcc_renderer_set_force_no_ruby(p_renderer, p_sys->b_cfg_ignore_ruby);
     aribcc_renderer_set_stroke_width(p_renderer, p_sys->f_cfg_stroke_width);
 
-    if (p_sys->psz_cfg_font_name && strlen(p_sys->psz_cfg_font_name) > 0) {
+    if (p_sys->psz_cfg_font_name) {
         const char* font_families[] = { p_sys->psz_cfg_font_name };
         aribcc_renderer_set_default_font_family(p_renderer, font_families, 1, true);
     }