switch ecryptfs_write() to struct inode *, kill on-stack fake files

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/ecryptfs/ecryptfs_kernel.h b/fs/ecryptfs/ecryptfs_kernel.h
index 84dd2f8..0032a9f 100644
--- a/fs/ecryptfs/ecryptfs_kernel.h
+++ b/fs/ecryptfs/ecryptfs_kernel.h
@@ -731,8 +731,7 @@
 int ecryptfs_write_lower_page_segment(struct inode *ecryptfs_inode,
 				      struct page *page_for_lower,
 				      size_t offset_in_page, size_t size);
-int ecryptfs_write(struct file *ecryptfs_file, char *data, loff_t offset,
-		   size_t size);
+int ecryptfs_write(struct inode *inode, char *data, loff_t offset, size_t size);
 int ecryptfs_read_lower(char *data, loff_t offset, size_t size,
 			struct inode *ecryptfs_inode);
 int ecryptfs_read_lower_page_segment(struct page *page_for_ecryptfs,