dt-bindings: qcom: smb1355: Add bindings

Add bindings of the smb1355-charger driver as of msm-4.14
'commit 7e16ff6c ("defconfig: qcs405: enable WLAN configs
for 32-bit QCS405")'.

Change-Id: Id5adaa2e850591936e72dcf126007c1bc5ef5285
Signed-off-by: Guru Das Srinagesh <gurus@codeaurora.org>