sparc: explicitly cast negative phandle checks to s32

When we switched sparc from using 'int's to 'phandle's (which is a u32), we
neglected to do anything with the various checks for -1.  For those tests,
explicitly cast the phandles to s32.

Signed-off-by: Andres Salomon <dilinger@queued.net>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
diff --git a/arch/sparc/prom/tree_64.c b/arch/sparc/prom/tree_64.c
index d936600..92204c3 100644
--- a/arch/sparc/prom/tree_64.c
+++ b/arch/sparc/prom/tree_64.c
@@ -43,10 +43,10 @@
 {
 	phandle cnode;
 
-	if (node == -1)
+	if ((s32)node == -1)
 		return 0;
 	cnode = __prom_getchild(node);
-	if (cnode == -1)
+	if ((s32)cnode == -1)
 		return 0;
 	return cnode;
 }
@@ -56,10 +56,10 @@
 {
 	phandle cnode;
 
-	if (node == -1)
+	if ((s32)node == -1)
 		return 0;
 	cnode = prom_node_to_node("parent", node);
-	if (cnode == -1)
+	if ((s32)cnode == -1)
 		return 0;
 	return cnode;
 }
@@ -76,10 +76,10 @@
 {
 	phandle sibnode;
 
-	if (node == -1)
+	if ((s32)node == -1)
 		return 0;
 	sibnode = __prom_getsibling(node);
-	if (sibnode == -1)
+	if ((s32)sibnode == -1)
 		return 0;
 
 	return sibnode;
@@ -240,7 +240,7 @@
 	unsigned long args[7];
 
 	*buffer = 0;
-	if (node == -1)
+	if ((s32)node == -1)
 		return buffer;
 
 	args[0] = (unsigned long) prom_nextprop_name;
@@ -266,7 +266,7 @@
 	unsigned long args[7];
 	char buf[32];
 
-	if (node == -1) {
+	if ((s32)node == -1) {
 		*buffer = 0;
 		return buffer;
 	}
@@ -369,7 +369,7 @@
 	p1275_cmd_direct(args);
 
 	node = (int) args[4];
-	if (node == -1)
+	if ((s32)node == -1)
 		return 0;
 	return node;
 }