dm: add cells_count parameter in *_count_phandle_with_args

The cell_count argument is required when cells_name is NULL.

This patch adds this parameter in live tree API
- of_count_phandle_with_args
- ofnode_count_phandle_with_args
- dev_count_phandle_with_args

This parameter solves issue when these API is used to count
the number of element of a cell without cell name. This parameter
allow to force the size cell.

For example:
  count = dev_count_phandle_with_args(dev, "array", NULL, 3);

Signed-off-by: Patrick Delaunay <patrick.delaunay@st.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/drivers/usb/host/ehci-generic.c b/drivers/usb/host/ehci-generic.c
index 304a343..c93a705 100644
--- a/drivers/usb/host/ehci-generic.c
+++ b/drivers/usb/host/ehci-generic.c
@@ -86,7 +86,7 @@
 	err = 0;
 	priv->clock_count = 0;
 	clock_nb = ofnode_count_phandle_with_args(dev_ofnode(dev), "clocks",
-						  "#clock-cells");
+						  "#clock-cells", 0);
 	if (clock_nb > 0) {
 		priv->clocks = devm_kcalloc(dev, clock_nb, sizeof(struct clk),
 					    GFP_KERNEL);
@@ -116,7 +116,7 @@
 
 	priv->reset_count = 0;
 	reset_nb = ofnode_count_phandle_with_args(dev_ofnode(dev), "resets",
-						  "#reset-cells");
+						  "#reset-cells", 0);
 	if (reset_nb > 0) {
 		priv->resets = devm_kcalloc(dev, reset_nb,
 					    sizeof(struct reset_ctl),