soc: qcom: rpmh-rsc: Remove tcs_is_free() API

soc: qcom: rpmh-rsc: Remove tcs_is_free() API

This API does very little. Let's replace all the callsites with the
normal operations that would be done on top of the bitmap that
tcs_in_use is. This simplifies and reduces the code size.

Reviewed-by: Maulik Shah <mkshah@codeaurora.org>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Cc: Maulik Shah <mkshah@codeaurora.org>
Cc: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
Link: https://lore.kernel.org/r/20200521060425.24285-2-swboyd@chromium.org
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>