charge_manager: handle gracefully dedicated port
charge_manager: handle gracefully dedicated port

charge_manager_fill_power_info can be called to fill the power info
of the dedicated port. This function might call
charge_manager_get_source_current with the dedicated port, we don't
want to use assert in that case, but just fail gracefully by returning
0.

BRANCH=None
BUG=chromium:841944
TEST=Check that the function returns 0 for dedicated and not 0 for USB.

Change-Id: I357c056647e01bdb0e77a08a6c6b492aa3dbb503
Signed-off-by: Fabien Parent <87a7dbc742813827439862785b5496d58d13f880@baylibre.com>
Reviewed-on: https://chromium-review.googlesource.com/1059248
Reviewed-by: Daisuke Nojiri <fd5f93af191bf7e8f73ea71cc3c0f66b41b1dd49@chromium.org>

coreboot/chrome-ec,coreboot/chrome-ec,coreboot/chrome-ec,coreboot/chrome-ec,coreboot/chrome-ec,coreboot/chrome-ec