blackfin: Add <asm/clock.h> to numerous drivers

With d6a320d we moved some clock externs out of blackfin_local.h and
into clock.h but now need to include <asm/clock.h> in more drivers to
avoid warnings.

Cc: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Tom Rini <trini@ti.com>
diff --git a/drivers/block/pata_bfin.c b/drivers/block/pata_bfin.c
index 27ecaf4..b7fd1cd 100644
--- a/drivers/block/pata_bfin.c
+++ b/drivers/block/pata_bfin.c
@@ -12,6 +12,7 @@
 #include <command.h>
 #include <config.h>
 #include <asm/byteorder.h>
+#include <asm/clock.h>
 #include <asm/io.h>
 #include <asm/errno.h>
 #include <asm/portmux.h>