Remove HAVE_WAYLAND_ONLY dependency from searching and enabling backend module.

Summary:
this patch allows to enable wl_drm module(if it's exsited) without setting E_WL_FORCE as a wl_drm under HAVE_WAYLAND_ONLY.
this patch also prevent a crash under below condition. running enlightenment with HAVE_WAYLAND_ONLY option and without set E_WL_FORCE occurs crash where try to refer E_Manager because E_Manager is created in wl_drm module.

Reviewers: devilhorns

Subscribers: cedric

Differential Revision: https://phab.enlightenment.org/D1549

src/bin/e_comp.c

@@ -1051,6 +1051,7 @@ e_comp_init(void)
 
 #ifndef HAVE_WAYLAND_ONLY
    if (!e_comp_x_init())
+#endif
      {
         const char **test, *eng[] =
         {
@@ -1072,7 +1073,6 @@ e_comp_init(void)
           }
         return EINA_FALSE;
      }
-#endif
 #if defined(HAVE_WAYLAND_CLIENTS) || defined(HAVE_WAYLAND_ONLY)
    e_comp_wl_init();
 #endif