arm64: dts: apq8096-db820c: Increase load on l21 for SDCARD

In the same way as for msm8974-hammerhead, l21 load, used for SDCARD
VMMC, needs to be increased in order to prevent any voltage drop issues
(due to limited current) happening with some SDCARDS or during specific
operations (e.g. write).

Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Fixes: 660a9763 (arm64: dts: qcom: db820c: Add pm8994 regulator node)
Signed-off-by: Loic Poulain <loic.poulain@linaro.org>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>