staging: erofs: inline erofs_inode_is_data_compressed()

As a helper in erofs_fs.h, erofs_inode_is_data_compressed()
should be inlined.
Signed-off-by: Gao Xiang <gaoxiang25@huawei.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Link: https://lore.kernel.org/r/20190813023054.73126-1-gaoxiang25@huawei.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/erofs/erofs_fs.h

@@ -62,7 +62,7 @@ enum {
 	EROFS_INODE_LAYOUT_MAX
 };
 
-static bool erofs_inode_is_data_compressed(unsigned int datamode)
+static inline bool erofs_inode_is_data_compressed(unsigned int datamode)
 {
 	if (datamode == EROFS_INODE_FLAT_COMPRESSION)
 		return true;