arm64: dts: qcom: msm8994: Fix sleep clock name

The sleep clock name expected by GCC is actually "sleep" and not
"sleep_clk". Fix the clock-names value for it to make sure it is
provided.

Fixes: 9204da57cd65 ("arm64: dts: qcom: msm8994: Provide missing "xo_board" and "sleep_clk" to GCC")

Signed-off-by: Konrad Dybcio <konrad.dybcio@somainline.org>
Reviewed-by: Petr Vorel <petr.vorel@gmail.com>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Link: https://lore.kernel.org/r/20220319174645.340379-2-konrad.dybcio@somainline.org