Improve portability

1) Remove the double parentheses around two comparisons in checks.c.
   The OSX LLVM-based C compiler warns about them.
2) Put an explicit "=" in the TN() macro, in accordance with c99.

Signed-off-by: Phil Elwell <phil@raspberrypi.org>

checks.c

@@ -624,11 +624,11 @@ static void check_avoid_default_addr_size(struct check *c, struct node *dt,
 	if (!reg && !ranges)
 		return;
 
-	if ((node->parent->addr_cells == -1))
+	if (node->parent->addr_cells == -1)
 		FAIL(c, "Relying on default #address-cells value for %s",
 		     node->fullpath);
 
-	if ((node->parent->size_cells == -1))
+	if (node->parent->size_cells == -1)
 		FAIL(c, "Relying on default #size-cells value for %s",
 		     node->fullpath);
 }

fdtdump.c

@@ -22,7 +22,7 @@
 static const char *tagname(uint32_t tag)
 {
 	static const char * const names[] = {
-#define TN(t) [t] #t
+#define TN(t) [t] = #t
 		TN(FDT_BEGIN_NODE),
 		TN(FDT_END_NODE),
 		TN(FDT_PROP),