f2fs: enable inline data by default

Enable inline_data feature by default since it brings us better
performance and space utilization and now has already stable.
Add another option noinline_data to disable it during mount.

Suggested-by: Jaegeuk Kim <jaegeuk@kernel.org>
Suggested-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Wanpeng Li <wanpeng.li@linux.intel.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
diff --git a/Documentation/filesystems/f2fs.txt b/Documentation/filesystems/f2fs.txt
index 48e2123..e9e750e 100644
--- a/Documentation/filesystems/f2fs.txt
+++ b/Documentation/filesystems/f2fs.txt
@@ -144,6 +144,8 @@
                        as many as extent which map between contiguous logical
                        address and physical address per inode, resulting in
                        increasing the cache hit ratio.
+noinline_data          Disable the inline data feature, inline data feature is
+                       enabled by default.
 
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