ARM: provide an early platform initialization hook

This allows platforms to hook into the initialization early to setup
things like scheduler clocks, etc.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/arch/arm/kernel/setup.c b/arch/arm/kernel/setup.c
index e53132e..3455ad3 100644
--- a/arch/arm/kernel/setup.c
+++ b/arch/arm/kernel/setup.c
@@ -880,6 +880,9 @@
 #endif
 #endif
 	early_trap_init();
+
+	if (mdesc->init_early)
+		mdesc->init_early();
 }