cifs, msdos, vfat, hfs+: don't bother with parent in ->d_compare()

dentry->d_sb is just as good as parent->d_sb

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/fat/namei_msdos.c b/fs/fat/namei_msdos.c
index 1337c0c..0f17712 100644
--- a/fs/fat/namei_msdos.c
+++ b/fs/fat/namei_msdos.c
@@ -165,7 +165,7 @@
 static int msdos_cmp(const struct dentry *parent, const struct dentry *dentry,
 		unsigned int len, const char *str, const struct qstr *name)
 {
-	struct fat_mount_options *options = &MSDOS_SB(parent->d_sb)->options;
+	struct fat_mount_options *options = &MSDOS_SB(dentry->d_sb)->options;
 	unsigned char a_msdos_name[MSDOS_NAME], b_msdos_name[MSDOS_NAME];
 	int error;