arm64: dts: qcom: sc7280-herobrine: Consistently add "-regulator" suffix

Some of the fixed regulators were missing the "-regulator" suffix. Add
it to be consistent within the file and consistent with the fixed
regulators in sc7180-trogdor.

Signed-off-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Matthias Kaehlcke <mka@chromium.org>
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Link: https://lore.kernel.org/r/20220202132301.v3.2.I627e60c5488d54a45fd1482ca19f0f6e45192db2@changeid