regulator: cpr3-regulator: fix potential aging uninitialized variable usage

If cpr3_ctrl_clear_cpr4_config() returns an error at the
beginning of the cpr3_regulator_measure_aging() function, then
goto cleanup is called.  After that, the *_restore values are
written back into hardware registers.  Unfortunately, these
*_restore variables are uninitialized in this code path.
Correct this issue.

Change-Id: I906613a00137925c9903ac6c01771c459594864f
CRs-Fixed: 1066407
Signed-off-by: David Collins <collinsd@codeaurora.org>