MIPS: delay: Fix use of current_cpu_data in preemptable code.

This may lead to warnings like:

BUG: using smp_processor_id() in preemptible [00000000] code: reboot/1989
caller is __udelay+0x14/0x70
Call Trace:
[<ffffffff8110ad28>] dump_stack+0x8/0x34
[<ffffffff812dde04>] debug_smp_processor_id+0xf4/0x110
[<ffffffff812d90bc>] __udelay+0x14/0x70
[<ffffffff81378274>] md_notify_reboot+0x12c/0x148
[<ffffffff81161054>] notifier_call_chain+0x64/0xc8
[<ffffffff811614dc>] __blocking_notifier_call_chain+0x64/0xc0
[<ffffffff8115566c>] kernel_restart_prepare+0x1c/0x38
[<ffffffff811556cc>] kernel_restart+0x14/0x50
[<ffffffff8115581c>] SyS_reboot+0x10c/0x1f0
[<ffffffff81103684>] handle_sysn32+0x44/0x84

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

arch/mips/lib/delay.c

@@ -41,15 +41,15 @@ EXPORT_SYMBOL(__delay);
 
 void __udelay(unsigned long us)
 {
-	unsigned int lpj = current_cpu_data.udelay_val;
+	unsigned int lpj = raw_current_cpu_data.udelay_val;
 
 	__delay((us * 0x000010c7ull * HZ * lpj) >> 32);
 }
 EXPORT_SYMBOL(__udelay);
 
 void __ndelay(unsigned long ns)
 {
-	unsigned int lpj = current_cpu_data.udelay_val;
+	unsigned int lpj = raw_current_cpu_data.udelay_val;
 
 	__delay((ns * 0x00000005ull * HZ * lpj) >> 32);
 }