mfd: Fix tc6387xb resource reclaim

This patch includes below fixes:
1. add a missing iounmap in tc6387xb_probe() error path
2. fix resource reclaim in tc6387xb_remove()

Signed-off-by: Axel Lin <axel.lin@gmail.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>