The caps field depends on the mshcN alias ID but for some devices this
is unnecessary as the capabilities are the same for all instances
sharing the same compatible.

Add a common_caps field for this case which updates the host's
capabilities without needing the mshcN alias ID.
Signed-off-by: John Keeping <john@metanate.com>
Tested-by: Nicolas Frattaroli <frattaroli.nicolas@gmail.com>
Reviewed-by: Jaehoon Chung <jh80.chung@samsung.com>
Link: https://lore.kernel.org/r/20211124184603.3897245-2-john@metanate.comSigned-off-by: Ulf Hansson <ulf.hansson@linaro.org>