[IA64] Ensure that machvec is set up takes place before serial console

Parse the machvec command line option outside of the early_param()
so that ia64_mv is set before any console intialisation that
may result from early_param parsing.

Signed-off-by: Simon Horman <horms@verge.net.au>
Signed-off-by: Tony Luck <tony.luck@intel.com>

include/asm-ia64/machvec.h

@@ -275,6 +275,7 @@ struct ia64_machine_vector {
 
 extern struct ia64_machine_vector ia64_mv;
 extern void machvec_init (const char *name);
+extern void machvec_init_from_cmdline(const char *cmdline);
 
 # else
 #  error Unknown configuration.  Update asm-ia64/machvec.h.