conf: sdk_210209_defconfig: enable SENSORS_SFCTMP
The following patch added support for an SFC tmperature sensor:
Patch: https://github.com/starfive-tech/beagle_kernel_5.10/commit/b6b0e571705ba82560f604780646d24993aa56c0
However, the config needs to be enabled or the driver won't load.
Signed-off-by: Michael Scott <mike@foundries.io>