Smack: Remove unused inline function smk_ad_setfield_u_fs_path_mnt

commit a269434d ("LSM: separate LSM_AUDIT_DATA_DENTRY from LSM_AUDIT_DATA_PATH")
left behind this, remove it.
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>

security/smack/smack.h

@@ -497,10 +497,6 @@ static inline void smk_ad_setfield_u_fs_path_dentry(struct smk_audit_info *a,
 						    struct dentry *d)
 {
 }
-static inline void smk_ad_setfield_u_fs_path_mnt(struct smk_audit_info *a,
-						 struct vfsmount *m)
-{
-}
 static inline void smk_ad_setfield_u_fs_inode(struct smk_audit_info *a,
 					      struct inode *i)
 {