power: smb1351-charger: Add a DT entry to modify enable-pin polarity

Add ability to configure the polarity of enable-pin.

While at it, remove the debug register-dump call from probe
to avoid i2c failures in a parallel-charger configuration.

Change-Id: I5d0ba745bab95d064599606f81d3613066a9c394
Signed-off-by: Anirudh Ghayal <aghayal@codeaurora.org>