qpnp: revid: Add support to read TP Rev

Some PMICs software drivers (PM660) require the TP revision
information to implement specific logic. Add an optional
property qcom,tp-rev-valid to check if support for TP REV is
available in the REVID peripheral for the PMIC.

Change-Id: Ia7a344e60bedcc6fb28d9ed9f18dc29a3d7f4fd7
Signed-off-by: Rama Krishna Phani A <rphani@codeaurora.org>