keystone: ddr3: add ddr3.h to hold ddr3 API

It's convinient to hold ddr3 function definitions in separate file
such as ddr3.h. So move this from hardware.h to ddr3.h.

Acked-by: Murali Karicheri <m-karicheri2@ti.com>
Signed-off-by: Ivan Khoronzhuk <ivan.khoronzhuk@ti.com>
diff --git a/arch/arm/cpu/armv7/keystone/ddr3.c b/arch/arm/cpu/armv7/keystone/ddr3.c
index 4875db7..bb16551 100644
--- a/arch/arm/cpu/armv7/keystone/ddr3.c
+++ b/arch/arm/cpu/armv7/keystone/ddr3.c
@@ -7,10 +7,10 @@
  * SPDX-License-Identifier:     GPL-2.0+
  */
 
-#include <asm/arch/hardware.h>
 #include <asm/io.h>
+#include <asm/arch/ddr3.h>
 
-void init_ddrphy(u32 base, struct ddr3_phy_config *phy_cfg)
+void ddr3_init_ddrphy(u32 base, struct ddr3_phy_config *phy_cfg)
 {
 	unsigned int tmp;
 
@@ -57,7 +57,7 @@
 		;
 }
 
-void init_ddremif(u32 base, struct ddr3_emif_config *emif_cfg)
+void ddr3_init_ddremif(u32 base, struct ddr3_emif_config *emif_cfg)
 {
 	__raw_writel(emif_cfg->sdcfg,  base + KS2_DDR3_SDCFG_OFFSET);
 	__raw_writel(emif_cfg->sdtim1, base + KS2_DDR3_SDTIM1_OFFSET);