clk: qcom: gcc-sdm845: Populate the hwcg fields of branch clocks

Populate the hwcg_reg and hwcg_bit fields of the branch
clock structures for clocks which can be hardware clock
gated.

Change-Id: I2b59a4455cbcf82c77a4610bd63b28d93b32c5a8
Signed-off-by: Deepak Katragadda <dkatraga@codeaurora.org>