power: smb1390: optimize conditions to enable charger

Currently, SMB1390 always attempts to turn on switcher while a
Type-C source is attached, which can be of any charger type.
However, SMB1390 only works with QC3 and PPS adaptors.

Improve it, by only enabling switcher when SMB1390 SMB_EN pin
is pulled up for QC3 or PPS.

Change-Id: I79acb00c7299fdfad8eefb63f71fc6dc4573b45d
Signed-off-by: Harry Yang <harryy@codeaurora.org>