drm/st7571-i2c: select CONFIG_DRM_CLIENT_SELECTION

The newly added driver calls drm_client_setup(), but that is not
always built in:

x86_64-linux-ld: vmlinux.o: in function `st7571_probe':
st7571-i2c.c:(.text+0x7b7119): undefined reference to `drm_client_setup'

Select the appropriate Kconfig symbol.

Fixes: 4b35f0f ("drm/st7571-i2c: add support for Sitronix ST7571 LCD controller")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Reviewed-by: Marcus Folkesson <marcus.folkesson@gmail.com>
Link: https://lore.kernel.org/r/20250428150752.3970145-1-arnd@kernel.org
Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>

Author: arndb

drivers/gpu/drm/tiny/Kconfig

@@ -215,6 +215,7 @@ config TINYDRM_ST7586
 config DRM_ST7571_I2C
 	tristate "DRM support for Sitronix ST7571 display panels (I2C)"
 	depends on DRM && I2C && MMU
+	select DRM_CLIENT_SELECTION
 	select DRM_GEM_SHMEM_HELPER
 	select DRM_KMS_HELPER
 	select REGMAP_I2C