common: fdt: Make fdt_del_subnodes/fdt_del_partition static

These functions are only called in this file that's why make them static
to keep static analysers happy.

Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/common/fdt_support.c b/common/fdt_support.c
index 1bdd03f..34d2bd5 100644
--- a/common/fdt_support.c
+++ b/common/fdt_support.c
@@ -725,7 +725,7 @@
 	unsigned int r1;
 };
 
-int fdt_del_subnodes(const void *blob, int parent_offset)
+static int fdt_del_subnodes(const void *blob, int parent_offset)
 {
 	int off, ndepth;
 	int ret;
@@ -750,7 +750,7 @@
 	return 0;
 }
 
-int fdt_del_partitions(void *blob, int parent_offset)
+static int fdt_del_partitions(void *blob, int parent_offset)
 {
 	const void *prop;
 	int ndepth = 0;