dt/flattree: explicitly pass command line pointer to early_init_dt_scan_chosen

This patch drops the reference to a global 'cmd_line' variable from
early_init_dt_scan_chosen, and instead passes the pointer to the command
line string via the *data argument.  Each architecture does something
slightly different with the initial command line, so it makes sense for
the architecture to be able to specify the variable name.

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
diff --git a/drivers/of/fdt.c b/drivers/of/fdt.c
index 8b63a69..65200af 100644
--- a/drivers/of/fdt.c
+++ b/drivers/of/fdt.c
@@ -670,7 +670,7 @@
 
 	pr_debug("search \"chosen\", depth: %d, uname: %s\n", depth, uname);
 
-	if (depth != 1 ||
+	if (depth != 1 || !data ||
 	    (strcmp(uname, "chosen") != 0 && strcmp(uname, "chosen@0") != 0))
 		return 0;
 
@@ -679,16 +679,16 @@
 	/* Retrieve command line */
 	p = of_get_flat_dt_prop(node, "bootargs", &l);
 	if (p != NULL && l > 0)
-		strlcpy(cmd_line, p, min((int)l, COMMAND_LINE_SIZE));
+		strlcpy(data, p, min((int)l, COMMAND_LINE_SIZE));
 
 #ifdef CONFIG_CMDLINE
 #ifndef CONFIG_CMDLINE_FORCE
 	if (p == NULL || l == 0 || (l == 1 && (*p) == 0))
 #endif
-		strlcpy(cmd_line, CONFIG_CMDLINE, COMMAND_LINE_SIZE);
+		strlcpy(data, CONFIG_CMDLINE, COMMAND_LINE_SIZE);
 #endif /* CONFIG_CMDLINE */
 
-	pr_debug("Command line is: %s\n", cmd_line);
+	pr_debug("Command line is: %s\n", (char*)data);
 
 	/* break now */
 	return 1;