power: supply: bq25890_charger: Read external power props on probe

Signed-off-by: Sebastian Krzyszkowiak <sebastian.krzyszkowiak@puri.sm>
2 jobs for probe-pd in 66 minutes and 32 seconds (queued for 2 seconds)
Status Job ID Name Coverage
  Build
passed #366879
librem5
build:aarch64

00:19:55

passed #366880
librem5:arm64
build:deb

01:06:32