[PATCH] drm/bridge/sii8620: fix link error

[Tobias Regnery <tobias.regnery@gmail.com>]

With CONFIG_EXTCON=m and CONFIG_DRM_SIL_SII8620=y we see the following link
error:

drivers/gpu/drm/bridge/sil-sii8620.o: In function `sii8620_remove':
sil-sii8620.c:(.text+0xd5): undefined reference to `extcon_unregister_notifier'
drivers/gpu/drm/bridge/sil-sii8620.o: In function `sii8620_probe':
sil-sii8620.c:(.text+0x2a4b): undefined reference to `extcon_find_edev_by_node'
sil-sii8620.c:(.text+0x2af4): undefined reference to `extcon_register_notifier'
drivers/gpu/drm/bridge/sil-sii8620.o: In function `sii8620_extcon_work':
sil-sii8620.c:(.text+0x2b94): undefined reference to `extcon_get_state'

Fix this by selecting EXTCON.

Fixes: 688838442147 ("drm/bridge/sii8620: use micro-USB cable detection logic to detect MHL")
Signed-off-by: Tobias Regnery <tobias.regnery@gmail.com>
---
 drivers/gpu/drm/bridge/Kconfig | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/gpu/drm/bridge/Kconfig b/drivers/gpu/drm/bridge/Kconfig
index 3aa65bdecb0e..ab99e36ee034 100644
--- a/drivers/gpu/drm/bridge/Kconfig
+++ b/drivers/gpu/drm/bridge/Kconfig
@@ -74,6 +74,7 @@ config DRM_SIL_SII8620
 	tristate "Silicon Image SII8620 HDMI/MHL bridge"
 	depends on OF && RC_CORE
 	select DRM_KMS_HELPER
+	select EXTCON
 	help
 	  Silicon Image SII8620 HDMI/MHL bridge chip driver.
 
-- 
2.17.0