ARM: 5916/1: ARM: L2 : Add maintainace by line helper functions

This patch adds the cache maintainance by line helper functions.

Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>