Some branch clocks are governed externally and we're only supposed to
send a request concerning their shutdown, not actually ensure it happens.

Use the BRANCH_HALT_SKIP define to skip checking the halt bit.
Reviewed-by: Jeffrey Hugo <quic_jhugo@quicinc.com>
Signed-off-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Link: https://lore.kernel.org/r/20230622-topic-8998clk-v2-6-6222fbc2916b@linaro.orgSigned-off-by: Bjorn Andersson <andersson@kernel.org>