nwl: Don't turn off clocks and phy on screen blank

This makes the display turn on again on unblank like

    echo 1 > /sys/class/graphics/fb0/blank ; sleep 1; echo 0 > /sys/class/graphics/fb0/blank

Closes: #32

Signed-off-by: Guido Günther <guido.gunther@puri.sm>
2 jobs for imx8-4.18-devkit-dsi-no_clk_reset in 48 minutes and 19 seconds (queued for 2 seconds)
Status Job ID Name Coverage
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passed #17684
librem5
build:aarch64:Image

00:48:19

passed #17685
librem5
build:aarch64:deb

00:36:53