Revert "Revert "Release cblocks back to the free pool""

This reverts commit 516cb2d025a8c5dc67f4a926bdbb79c0e3725b4c.

Reason for revert: Add back after merging f2fs/f2fs-tools changes removing immutable bit stuffs

Bug: 188928405
Change-Id: I6a6fcde1190bff14abe1a67a75b8e7be95d89072
7 files changed