ARM: shmobile: Common shmobile_scu_base in headsmp-scu.S

Update the code in headsmp-scu.S to use a global
shmobile_scu_base variable both for convenient SCU
base address storage and for the early SCU setup
code in shmobile_secondary_vector_scu.

With this patch applied r8a7779, sh73a0 and EMEV2
all make use of the global shmobile_scu_base
variable. However only sh73a0 makes use of the SCU
bring up code in shmobile_secondary_vector_scu.

Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
diff --git a/arch/arm/mach-shmobile/include/mach/common.h b/arch/arm/mach-shmobile/include/mach/common.h
index 20acf00..84dcaa4 100644
--- a/arch/arm/mach-shmobile/include/mach/common.h
+++ b/arch/arm/mach-shmobile/include/mach/common.h
@@ -95,6 +95,7 @@
 static inline int shmobile_cpu_is_dead(unsigned int cpu) { return 1; }
 #endif
 
+extern void __iomem *shmobile_scu_base;
 extern void shmobile_smp_init_cpus(unsigned int ncores);
 
 static inline void __init shmobile_init_late(void)