ecore_drm: Making _ecore_drm_init_count not to go below zero in _ecore_drm_shutdown.

Summary:
If _ecore_drm_init_count goes below zero, then when next time ecore_drm_init is called, it won't do the initializations which it is supposed to do. So preventing this scenario by not making it go
below zero in _ecore_wl_shutdown function.

@fix

Signed-off-by: Srivardhan Hebbar <sri.hebbar@samsung.com>

Reviewers: devilhorns

Reviewed By: devilhorns

Subscribers: cedric

Differential Revision: https://phab.enlightenment.org/D1573

src/lib/ecore_drm/ecore_drm.c

@@ -102,6 +102,9 @@ log_err:
 EAPI int 
 ecore_drm_shutdown(void)
 {
+   /* _ecore_drm_init_count should not go below zero. */
+   if (_ecore_drm_init_count < 1) return 0;
+
    /* if we are still in use, decrement init count and get out */
    if (--_ecore_drm_init_count != 0) return _ecore_drm_init_count;