The TCSR mutex bindings allow device to be described only with address
space (so it uses MMIO, not syscon regmap).  This seems reasonable, as
TCSR mutex is actually a dedicated IO address space, and it also fixes
DT schema checks:

  qcom-msm8974-sony-xperia-rhine-amami.dtb: tcsr-mutex: 'reg' is a required property
  qcom-msm8974-sony-xperia-rhine-amami.dtb: tcsr-mutex: 'syscon' does not match any of the regexes: 'pinctrl-[0-9]+'
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Tested-by: Luca Weiss <luca@z3ntu.xyz> # fairphone-fp2
Signed-off-by: Bjorn Andersson <andersson@kernel.org>
Link: https://lore.kernel.org/r/20220920150414.637634-4-krzysztof.kozlowski@linaro.org