dt-bindings: regulator: qcom,rpmh-regulator: allow i, j, l, m & n as RPMh resource name suffix

Add "i", "j", "l", "m" and "n" to the allowed subffix list as they can be
used as RPMh resource name suffixes on new platforms.

Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org>
Acked-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Link: https://lore.kernel.org/r/20230822-topic-sm8x50-upstream-rpmh-regulator-suffix-v2-1-136b315085a4@linaro.org


Signed-off-by: Mark Brown <broonie@kernel.org>