power: qpnp-fg-gen4: Add TTF support for step charging

Add TTF support for step charging by reading the parameters
from the battery profile and notifying the parameters when TTF
algorithm queries for the mode.

Change-Id: Ibe8a6ec41444735a7d4fc8392ed6a0f9caaf1dc3
Signed-off-by: Subbaraman Narayanamurthy <subbaram@codeaurora.org>