drm/sti: Remove local fbdev emulation Kconfig option

DRM_STI_FBDEV config is currently used to enable/disable fbdev emulation
for the sti kms driver.

Remove this local config option and use the core fb helpers with
drm_kms_helper.fbdev_emulation module option to enable/disable fbdev
at runtime.

Signed-off-by: Archit Taneja <architt@codeaurora.org>
Reviewed-by: Vincent Abriou <vincent.abriou@st.com>
diff --git a/drivers/gpu/drm/sti/sti_drv.c b/drivers/gpu/drm/sti/sti_drv.c
index 105e7e54b..45c6375 100644
--- a/drivers/gpu/drm/sti/sti_drv.c
+++ b/drivers/gpu/drm/sti/sti_drv.c
@@ -160,11 +160,10 @@
 
 	drm_mode_config_reset(dev);
 
-#ifdef CONFIG_DRM_STI_FBDEV
 	drm_fbdev_cma_init(dev, 32,
 			   dev->mode_config.num_crtc,
 			   dev->mode_config.num_connector);
-#endif
+
 	return 0;
 }