[MIPS] time: Add GT641xx timer0 clockevent driver

And make use of it for Cobalt.  A few others such as the Malta could make
use of it as well.

Signed-off-by: Yoichi Yuasa <yoichi_yuasa@tripeaks.co.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
diff --git a/arch/mips/cobalt/Makefile b/arch/mips/cobalt/Makefile
index 6b83f4d..d73833b 100644
--- a/arch/mips/cobalt/Makefile
+++ b/arch/mips/cobalt/Makefile
@@ -2,7 +2,7 @@
 # Makefile for the Cobalt micro systems family specific parts of the kernel
 #
 
-obj-y := buttons.o irq.o led.o reset.o rtc.o serial.o setup.o
+obj-y := buttons.o irq.o led.o reset.o rtc.o serial.o setup.o time.o
 
 obj-$(CONFIG_PCI)		+= pci.o
 obj-$(CONFIG_EARLY_PRINTK)	+= console.o