ARM: imx5: use dynamic mapping for CCM block

ARM: imx5: use dynamic mapping for CCM block

Replace the static mapping of CCM block with dynamic mapping and
retrieve CCM base address from device tree.  Though it's not nice to
encode the variable ccm_base in macros, it helps to avoid a massive
churn on the code.

Signed-off-by: Shawn Guo <shawn.guo@freescale.com>