power: qpnp-fg: fix capacity learning wake-up source handling

In case of hardware coulomb counting based capacity learning the
wake-up source is not released in error conditions. Fix the same.

CRs-Fixed: 977956
Change-Id: I816642281aa2663b504ef3532653ff49aecc4f30
Signed-off-by: Ashay Jaiswal <ashayj@codeaurora.org>