[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/gt64120/wrppmc/time.c b/arch/mips/gt64120/wrppmc/time.c
index c8ed57e..5b44085 100644
--- a/arch/mips/gt64120/wrppmc/time.c
+++ b/arch/mips/gt64120/wrppmc/time.c
@@ -26,7 +26,7 @@
 
 #define WRPPMC_CPU_CLK_FREQ 40000000 /* 40MHZ */
 
-void __init wrppmc_timer_setup(struct irqaction *irq)
+void __init plat_timer_setup(struct irqaction *irq)
 {
 	/* Install ISR for timer interrupt */
 	setup_irq(WRPPMC_MIPS_TIMER_IRQ, irq);