of: make of_fdt_is_compatible() static

The callers of of_fdt_is_compatible() are all in fdt.c so
make it static.
Signed-off-by: Frank Rowand <frank.rowand@sony.com>
Signed-off-by: Rob Herring <robh@kernel.org>

drivers/of/fdt.c

@@ -91,7 +91,7 @@ void of_fdt_limit_memory(int limit)
  * On match, returns a non-zero value with smaller values returned for more
  * specific compatible values.
  */
-int of_fdt_is_compatible(const void *blob,
+static int of_fdt_is_compatible(const void *blob,
 		      unsigned long node, const char *compat)
 {
 	const char *cp;

include/linux/of_fdt.h

@@ -31,9 +31,6 @@ extern void *of_fdt_get_property(const void *blob,
 				 unsigned long node,
 				 const char *name,
 				 int *size);
-extern int of_fdt_is_compatible(const void *blob,
-				unsigned long node,
-				const char *compat);
 extern bool of_fdt_is_big_endian(const void *blob,
 				 unsigned long node);
 extern int of_fdt_match(const void *blob, unsigned long node,