erofs-utils: add missing errors and normalize errors to lower-case

* Added useful error messages.
* Most errors start with lower-case, let's make all non-summarizing
  error messages lower-case for better consistency.
* Sorted default values in fsck's main function to match the struct.

Link: https://lore.kernel.org/r/20220129182204.26-1-igoreisberg@gmail.com
Link: https://lore.kernel.org/r/20220129194532.26-1-igoreisberg@gmail.com
Signed-off-by: Igor Ostapenko <igoreisberg@gmail.com>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
3 files changed