efl: remove eina_promise typedef

efl: remove eina_promise typedef

fixes the following warnings:
  /usr/local/include/efl-1/Efl_Model_Common.h:14:30: warning: redefinition of typedef 'Eina_Promise' is a
        C11 feature [-Wtypedef-redefinition]
  typedef struct _Eina_Promise Eina_Promise;
                               ^
  /usr/local/include/eina-1/eina/eina_promise.h:10:30: note: previous definition is here
  typedef struct _Eina_Promise Eina_Promise;

To remove the typedef i had to cleanup the includes of header in
evas_canvas3d_eet.c.