Add a new revision CHIP_REV_2_0.
Introudce macro is_mx6dqp, dqp means Dual/Quad Plus.
Since Dual/Quad Plus use same cpu type with Dual/Quad, but different
revision(Major Lower), we use this macro for Dual/Quad Plus.
Signed-off-by: Ye.Li <B37916@freescale.com>
Signed-off-by: Peng Fan <Peng.Fan@freescale.com>