arm: omap5: sdram: mark emif_get_ext_phy_ctrl_const_regs __weak

this will allow for boards to overwrite those
in case memory setup is different.

Signed-off-by: Felipe Balbi <balbi@ti.com>
Reviewed-by: Tom Rini <trini@ti.com>

arch/arm/cpu/armv7/omap5/sdram.c

@@ -513,7 +513,7 @@ const struct lpddr2_mr_regs mr_regs = {
 	.mr16	= MR16_REF_FULL_ARRAY
 };
 
-static void emif_get_ext_phy_ctrl_const_regs(u32 emif_nr,
+void __weak emif_get_ext_phy_ctrl_const_regs(u32 emif_nr,
 					     const u32 **regs,
 					     u32 *size)
 {