libata: trim trailing whitespace.

Also, fixup a tabs-to-spaces block of code in ata_piix.
diff --git a/include/linux/libata.h b/include/linux/libata.h
index 6cd9ba6..85b0aae 100644
--- a/include/linux/libata.h
+++ b/include/linux/libata.h
@@ -644,7 +644,7 @@
 	ap->ops->scr_write(ap, reg, val);
 }
 
-static inline void scr_write_flush(struct ata_port *ap, unsigned int reg, 
+static inline void scr_write_flush(struct ata_port *ap, unsigned int reg,
 				   u32 val)
 {
 	ap->ops->scr_write(ap, reg, val);