CONFIG_SYS_CLK_FREQ: Consistently be static or get_board_sys_clk()

This CONFIG option is used in one of two ways.  The first way is that it
is defined to a static value, of an unsigned long size.  The second way
is that it is defined to something, typically a function, to determine
this value at run time.

However, in a few cases that function returns a static value.  Change
that to using the static value directly.

In the case of using something at run time, convert everything to using
a function of the same name and prototype.  This will allow for further
cleanups.

Finally, we have a few cases where the function is just not used, so
drop it.

Signed-off-by: Tom Rini <trini@konsulko.com>
diff --git a/board/freescale/common/cadmus.h b/board/freescale/common/cadmus.h
index ddc2bb6..fb74e8f 100644
--- a/board/freescale/common/cadmus.h
+++ b/board/freescale/common/cadmus.h
@@ -19,7 +19,7 @@
 /*
  * Returns either 33000000 or 66000000 as the SYS_CLK_FREQ.
  */
-extern unsigned long get_clock_freq(void);
+extern unsigned long get_board_sys_clk(void);
 
 
 /*