[POWERPC] Add udbg support for RTAS console

Add udbg hooks for the RTAS console, based on the RTAS put-term-char
and get-term-char calls. Along with my previous patches, this should
enable debugging as soon as early_init_dt_scan_rtas() is called.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
diff --git a/include/asm-powerpc/udbg.h b/include/asm-powerpc/udbg.h
index 19a1517..55e5784 100644
--- a/include/asm-powerpc/udbg.h
+++ b/include/asm-powerpc/udbg.h
@@ -42,7 +42,8 @@
 extern void __init udbg_init_pmac_realmode(void);
 extern void __init udbg_init_maple_realmode(void);
 extern void __init udbg_init_iseries(void);
-extern void __init udbg_init_rtas(void);
+extern void __init udbg_init_rtas_panel(void);
+extern void __init udbg_init_rtas_console(void);
 
 #endif /* __KERNEL__ */
 #endif /* _ASM_POWERPC_UDBG_H */