fdt: Add a do_fixup_by_path_string() function

The do_fixup_by_path_string() will set the specified node's property to the
value contained in "status". It would just be an inline wrapper for
do_fixup_by_path() that calls strlen on the argument.

Signed-off-by: Chunhe Lan <Chunhe.Lan@freescale.com>
diff --git a/include/fdt_support.h b/include/fdt_support.h
index 8f06aac..0091dc3 100644
--- a/include/fdt_support.h
+++ b/include/fdt_support.h
@@ -36,6 +36,13 @@
 		      const void *val, int len, int create);
 void do_fixup_by_path_u32(void *fdt, const char *path, const char *prop,
 			  u32 val, int create);
+
+static inline void do_fixup_by_path_string(void *fdt, const char *path,
+					   const char *prop, const char *status)
+{
+	do_fixup_by_path(fdt, path, prop, status, strlen(status) + 1, 1);
+}
+
 void do_fixup_by_prop(void *fdt,
 		      const char *pname, const void *pval, int plen,
 		      const char *prop, const void *val, int len,