dt-bindings: qpnp-smb5: Support disabling of liquid presence detection

Provide option to turn off liquid presence detection on platforms that
do not support them.

Change-Id: I0d104c10eb9d3b5d6495d03963c39b7a5381c0c6
Signed-off-by: Guru Das Srinagesh <gurus@codeaurora.org>