arm: Move tbl to arch_global_data

Move this field into arch_global_data and tidy up.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/arch/mips/cpu/xburst/timer.c b/arch/mips/cpu/xburst/timer.c
index b6b3855..8ac8bf7 100644
--- a/arch/mips/cpu/xburst/timer.c
+++ b/arch/mips/cpu/xburst/timer.c
@@ -35,7 +35,7 @@
 {
 	/* reset time */
 	gd->lastinc = readl(&tcu->tcnt0);
-	gd->tbl = 0;
+	gd->arch.tbl = 0;
 }
 
 ulong get_timer_masked(void)
@@ -43,15 +43,15 @@
 	ulong now = readl(&tcu->tcnt0);
 
 	if (gd->lastinc <= now)
-		gd->tbl += now - gd->lastinc; /* normal mode */
+		gd->arch.tbl += now - gd->lastinc; /* normal mode */
 	else {
 		/* we have an overflow ... */
-		gd->tbl += TIMER_FDATA + now - gd->lastinc;
+		gd->arch.tbl += TIMER_FDATA + now - gd->lastinc;
 	}
 
 	gd->lastinc = now;
 
-	return gd->tbl;
+	return gd->arch.tbl;
 }
 
 void udelay_masked(unsigned long usec)
@@ -95,7 +95,7 @@
 	writeb(1 << TIMER_CHAN, &tcu->tesr); /* start counting up */
 
 	gd->lastinc = 0;
-	gd->tbl = 0;
+	gd->arch.tbl = 0;
 
 	return 0;
 }
@@ -112,7 +112,7 @@
 
 void set_timer(ulong t)
 {
-	gd->tbl = t;
+	gd->arch.tbl = t;
 }
 
 void __udelay(unsigned long usec)