arm64: dts: qcom: pm660l: Remove board-specific WLED configuration

This string- and electrical configuration depend on the board and panel,
and should hence not be defined generically for every user of pm660l.
SoMainline will pick this configuration again when enabling WLED on the
Sony Nile platform.

Fixes: 7b56a804 ("arm64: dts: qcom: pm660l: Add WLED support")
Signed-off-by: Marijn Suijten <marijn.suijten@somainline.org>
Reviewed-By: AngeloGioacchino Del Regno <angelogioacchino.delregno@somainline.org>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Link: https://lore.kernel.org/r/20211007213400.258371-14-marijn.suijten@somainline.org