MIPS: remove orphan sb1250_time_init() declaration

All uses of sb1250_time_init() have been removed by
commit d527eef5 ("[MIPS] Sibyte: Finish conversion to modern
time APIs."), so remove the orphan declaration.

The comments about sb1250_time_init() is useless in arch_init_irq(),
so remove these comments.
Signed-off-by: Gaosheng Cui <cuigaosheng1@huawei.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

arch/mips/include/asm/sibyte/sb1250.h

@@ -32,7 +32,6 @@ extern unsigned int soc_type;
 extern unsigned int periph_rev;
 extern unsigned int zbbus_mhz;
 
-extern void sb1250_time_init(void);
 extern void sb1250_mask_irq(int cpu, int irq);
 extern void sb1250_unmask_irq(int cpu, int irq);
 

arch/mips/sibyte/sb1250/irq.c

@@ -262,12 +262,6 @@ void __init arch_init_irq(void)
 	__raw_writeq(tmp, IOADDR(A_IMR_REGISTER(0, R_IMR_INTERRUPT_MASK)));
 	__raw_writeq(tmp, IOADDR(A_IMR_REGISTER(1, R_IMR_INTERRUPT_MASK)));
 
-	/*
-	 * Note that the timer interrupts are also mapped, but this is
-	 * done in sb1250_time_init().	Also, the profiling driver
-	 * does its own management of IP7.
-	 */
-
 	/* Enable necessary IPs, disable the rest */
 	change_c0_status(ST0_IM, imask);
 }