nxp: Migrate CONFIG_DDR_CLK_FREQ to Kconfig

As this symbol can either be a fixed value or the function
get_board_ddr_clk, migration is tricky.  Introduce a choice of DYNAMIC
or STATIC_DDR_CLK_FREQ.  If DYNAMIC, we continue to use the board
defined get_board_ddr_clk function.  If STATIC, set CONFIG_DDR_CLK_FREQ
to that value and now include/clock_legacy.h contains the function
prototype or defines get_board_ddr_clk() to that static value.  Update
callers to test for DYNAMIC or STATIC.

Signed-off-by: Tom Rini <trini@konsulko.com>
diff --git a/arch/powerpc/cpu/mpc85xx/cpu.c b/arch/powerpc/cpu/mpc85xx/cpu.c
index 610a8ec..cd32290 100644
--- a/arch/powerpc/cpu/mpc85xx/cpu.c
+++ b/arch/powerpc/cpu/mpc85xx/cpu.c
@@ -11,6 +11,7 @@
 #include <config.h>
 #include <common.h>
 #include <cpu_func.h>
+#include <clock_legacy.h>
 #include <init.h>
 #include <irq_func.h>
 #include <log.h>
@@ -52,7 +53,8 @@
 	uint major, minor;
 	struct cpu_type *cpu;
 	char buf1[32], buf2[32];
-#if defined(CONFIG_DDR_CLK_FREQ) || defined(CONFIG_FSL_CORENET)
+#if defined(CONFIG_DYNAMIC_DDR_CLK_FREQ) || \
+	defined(CONFIG_STATIC_DDR_CLK_FREQ) || defined(CONFIG_FSL_CORENET)
 	ccsr_gur_t __iomem *gur =
 		(void __iomem *)(CONFIG_SYS_MPC85xx_GUTS_ADDR);
 #endif
@@ -70,12 +72,12 @@
 		>> FSL_CORENET_RCWSR5_DDR_SYNC_SHIFT;
 #endif /* CONFIG_SYS_FSL_QORIQ_CHASSIS2 */
 #else	/* CONFIG_FSL_CORENET */
-#ifdef CONFIG_DDR_CLK_FREQ
+#if defined(CONFIG_DYNAMIC_DDR_CLK_FREQ) || defined(CONFIG_STATIC_DDR_CLK_FREQ)
 	u32 ddr_ratio = ((gur->porpllsr) & MPC85xx_PORPLLSR_DDR_RATIO)
 		>> MPC85xx_PORPLLSR_DDR_RATIO_SHIFT;
 #else
 	u32 ddr_ratio = 0;
-#endif /* CONFIG_DDR_CLK_FREQ */
+#endif /* CONFIG_DYNAMIC_DDR_CLK_FREQ || CONFIG_STATIC_DDR_CLK_FREQ */
 #endif /* CONFIG_FSL_CORENET */
 
 	unsigned int i, core, nr_cores = cpu_numcores();