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/arch/mips/include/asm/prom.h b/arch/mips/include/asm/prom.h
index f29b862..857d9b7 100644
--- a/arch/mips/include/asm/prom.h
+++ b/arch/mips/include/asm/prom.h
@@ -14,9 +14,6 @@
 #ifdef CONFIG_OF
 #include <asm/bootinfo.h>
 
-/* which is compatible with the flattened device tree (FDT) */
-#define cmd_line arcs_cmdline
-
 extern int early_init_dt_scan_memory_arch(unsigned long node,
 	const char *uname, int depth, void *data);
 
diff --git a/arch/mips/kernel/prom.c b/arch/mips/kernel/prom.c
index a19811e9..5b7eade 100644
--- a/arch/mips/kernel/prom.c
+++ b/arch/mips/kernel/prom.c
@@ -83,7 +83,8 @@
 	 * device-tree, including the platform type, initrd location and
 	 * size, and more ...
 	 */
-	of_scan_flat_dt(early_init_dt_scan_chosen, NULL);
+	of_scan_flat_dt(early_init_dt_scan_chosen, arcs_cmdline);
+
 
 	/* Scan memory nodes */
 	of_scan_flat_dt(early_init_dt_scan_root, NULL);