mfd: da9150: Use relative paths in DT bindings document
When referencing other DT bindings documentation, use relative
path rather than absolute.
Suggested-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Adam Thomson <Adam.Thomson.Opensource@diasemi.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
authored by