ARM: dts: qcom: ipq4019: add more labels

Lets add labels to more commonly used nodes for easier modification in board DTS files.

Signed-off-by: Robert Marko <robert.marko@sartura.hr>
Cc: Luka Perkov <luka.perkov@sartura.hr>
Link: https://lore.kernel.org/r/20200909195640.3127341-2-robert.marko@sartura.hr


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