blackfin: Set correct early debug serial baudrate.

Calculate the early uart clock from the system clock registers set by
the bootrom other than the predefine uboot clock macros.

Split the early baudrate setting function and the normal baudrate
setting one.

Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
diff --git a/arch/blackfin/lib/clocks.c b/arch/blackfin/lib/clocks.c
index d852f5e..97795e1 100644
--- a/arch/blackfin/lib/clocks.c
+++ b/arch/blackfin/lib/clocks.c
@@ -7,17 +7,7 @@
  */
 
 #include <common.h>
-#include <asm/blackfin.h>
-
-#ifdef PLL_CTL
-# include <asm/mach-common/bits/pll.h>
-# define pll_is_bypassed() (bfin_read_PLL_STAT() & DF)
-#else
-# include <asm/mach-common/bits/cgu.h>
-# define pll_is_bypassed() (bfin_read_CGU_STAT() & PLLBP)
-# define bfin_read_PLL_CTL() bfin_read_CGU_CTL()
-# define bfin_read_PLL_DIV() bfin_read_CGU_DIV()
-#endif
+#include <asm/clock.h>
 
 /* Get the voltage input multiplier */
 u_long get_vco(void)