qpnp-fg-gen3: Fix storing nominal capacity to actual capacity

Currently, nominal capacity is stored back to the actual capacity
only when the actual capacity is non-zero. However, that can be
true when the battery is inserted for the first time. This makes
the actual capacity to be stored only when a capacity learning
cycle completes. Other algorithms like to use actual capacity
before that. Fix it.

Change-Id: I346085ec722f491f96181ef1beb383710b441f4b
Signed-off-by: Subbaraman Narayanamurthy <subbaram@codeaurora.org>