MIPS: Move 'gic_frequency' to common location.

Move the global variable 'gic_frequency' to be defined in the file
'arch/mips/kernel/irq-gic.c' instead of defining it individually
for each platform making use of the GIC. Also change the type to
be an unsigned integer instead of signed.
Signed-off-by: Steven J. Hill <Steven.Hill@imgtec.com>

arch/mips/include/asm/gic.h

@@ -360,6 +360,7 @@ struct gic_shared_intr_map {
 #define GIC_PIN_TO_VEC_OFFSET	(1)
 
 extern unsigned int gic_present;
+extern unsigned int gic_frequency;
 extern unsigned long _gic_base;
 extern unsigned int gic_irq_base;
 extern unsigned int gic_irq_flags[];

arch/mips/kernel/irq-gic.c

@@ -19,6 +19,7 @@
 #include <linux/hardirq.h>
 #include <asm-generic/bitops/find.h>
 
+unsigned int gic_frequency;
 unsigned int gic_present;
 unsigned long _gic_base;
 unsigned int gic_irq_base;

arch/mips/mti-malta/malta-time.c

@@ -42,7 +42,6 @@
 #include <asm/mips-boards/maltaint.h>
 
 unsigned long cpu_khz;
-int gic_frequency;
 
 static int mips_cpu_timer_irq;
 static int mips_cpu_perf_irq;