drm/amd: Fix Kconfig indentation

Adjust indentation from spaces to tab (+optional two spaces) as in
coding style with command like:
    $ sed -e 's/^        /\t/' -i */Kconfig

Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/Kconfig

@@ -226,9 +226,9 @@ config DRM_AMDGPU
 	tristate "AMD GPU"
 	depends on DRM && PCI && MMU
 	select FW_LOADER
-        select DRM_KMS_HELPER
+	select DRM_KMS_HELPER
 	select DRM_SCHED
-        select DRM_TTM
+	select DRM_TTM
 	select POWER_SUPPLY
 	select HWMON
 	select BACKLIGHT_CLASS_DEVICE