drivers/ddr/fsl_ddr: Make SR_IE configurable

SR_IE(Self-refresh interrupt enable) is needed for
Hardware Based Self-Refresh. Make it configurable and let
board code handle the rest.

Signed-off-by: Joakim Tjernlund <joakim.tjernlund@transmode.se>
Reviewed-by: York Sun <yorksun@freescale.com>
diff --git a/drivers/ddr/fsl/ctrl_regs.c b/drivers/ddr/fsl/ctrl_regs.c
index 8367c95..8543679 100644
--- a/drivers/ddr/fsl/ctrl_regs.c
+++ b/drivers/ddr/fsl/ctrl_regs.c
@@ -858,7 +858,7 @@
 			break;
 		}
 	}
-
+	sr_ie = popts->self_refresh_interrupt_en;
 	num_pr = 1;	/* Make this configurable */
 
 	/*
diff --git a/include/fsl_ddr_sdram.h b/include/fsl_ddr_sdram.h
index e5b6e03..c79fce0 100644
--- a/include/fsl_ddr_sdram.h
+++ b/include/fsl_ddr_sdram.h
@@ -324,6 +324,8 @@
 	unsigned int dqs_config;	/* Use DQS? maybe only with DDR2? */
 	/* SREN - self-refresh during sleep */
 	unsigned int self_refresh_in_sleep;
+	/* SR_IE - Self-refresh interrupt enable */
+	unsigned int self_refresh_interrupt_en;
 	unsigned int dynamic_power;	/* DYN_PWR */
 	/* memory data width to use (16-bit, 32-bit, 64-bit) */
 	unsigned int data_bus_width;