[MIPS] Replace board_timer_setup function pointer by plat_timer_setup.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

---
diff --git a/arch/mips/kernel/smtc.c b/arch/mips/kernel/smtc.c
index 5b17a3d..604bcc5 100644
--- a/arch/mips/kernel/smtc.c
+++ b/arch/mips/kernel/smtc.c
@@ -577,7 +577,7 @@
 {
 	/*
 	 * Start timer on secondary VPEs if necessary.
-	 * mips_timer_setup should already have been invoked by init/main
+	 * plat_timer_setup has already have been invoked by init/main
 	 * on "boot" TC.  Like per_cpu_trap_init() hack, this assumes that
 	 * SMTC init code assigns TCs consdecutively and in ascending order
 	 * to across available VPEs.