ARM: dts: stm32: Update u-boot, boot-led for stm32mp157a-dk1-u-boot

As indicated in kernel led dt-bindings, label is a deprecated
property, so remove it and use blue led node's name instead
for u-boot,boot-led property.

Signed-off-by: Patrice Chotard <patrice.chotard@foss.st.com>
Reviewed-by: Patrick Delaunay <patrick.delaunay@foss.st.com>
1 file changed