common/f2fs: introduce _require_f2fs_io_command

Update existing f2fs testcases to utilize the new
_require_f2fs_io_command() helper for verifying required f2fs_io
subcommands instead of basic executable checks or open coding.

Suggested-by: Zorro Lang <zlang@kernel.org>
Signed-off-by: Chao Yu <chao@kernel.org>
Reviewed-by: Zorro Lang <zlang@kernel.org>
Signed-off-by: Zorro Lang <zlang@kernel.org>
10 files changed