security: update security_file_mmap() docs

This documents the fields added to security_file_mmap() that were
introduced in ed0321895182ffb6ecf210e066d87911b270d587.

Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: James Morris <jmorris@namei.org>

include/linux/security.h

@@ -590,6 +590,8 @@ static inline void security_free_mnt_opts(struct security_mnt_opts *opts)
  *	@reqprot contains the protection requested by the application.
  *	@prot contains the protection that will be applied by the kernel.
  *	@flags contains the operational flags.
+ *	@addr contains virtual address that will be used for the operation.
+ *	@addr_only contains a boolean: 0 if file-backed VMA, otherwise 1.
  *	Return 0 if permission is granted.
  * @file_mprotect:
  *	Check permissions before changing memory access permissions.