clk: qcom: clk-alpha-pll: Update set_rate for Zonda PLL

The Zonda PLL has a 16 bit signed alpha and in the cases where the alpha
value is greater than 0.5, the L value needs to be adjusted accordingly.
Thus update the logic to handle the signed alpha val.

Fixes: f21b6bfe ("clk: qcom: clk-alpha-pll: add support for zonda pll")
Cc: stable@vger.kernel.org
Signed-off-by: Satya Priya Kakitapalli <quic_skakitap@quicinc.com>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Link: https://lore.kernel.org/r/20240731062916.2680823-5-quic_skakitap@quicinc.com


Signed-off-by: Bjorn Andersson <andersson@kernel.org>