powerpc/pseries: Rename RAS_VECTOR_OFFSET to RTAS_VECTOR_EXTERNAL_INTERRUPT and move to rtas.h

The RAS code has a #define, RAS_VECTOR_OFFSET, that's used in the
check-exception RTAS call for the vector offset of the exception.

We'll be using this same vector offset for the upcoming IO Event interrupts
code (0x500) so let's move it to include/asm/rtas.h and call it
RTAS_VECTOR_EXTERNAL_INTERRUPT.

Signed-off-by: Mark Nelson <[e-mail]>
Signed-off-by: Benjamin Herrenschmidt <[e-mail]>

arch/powerpc/include/asm/rtas.h

···
 #define RTAS_TYPE_PMGM_CONFIG_CHANGE	0x70
 #define RTAS_TYPE_PMGM_SERVICE_PROC	0x71
 
+/* RTAS check-exception vector offset */
+#define RTAS_VECTOR_EXTERNAL_INTERRUPT	0x500
+
 struct rtas_error_log {
 	unsigned long version:8;		/* Architectural version */
 	unsigned long severity:3;		/* Severity level of error */

arch/powerpc/platforms/pseries/ras.c

···
 
 #define EPOW_SENSOR_TOKEN	9
 #define EPOW_SENSOR_INDEX	0
-#define RAS_VECTOR_OFFSET	0x500
 
 static irqreturn_t ras_epow_interrupt(int irq, void *dev_id);
 static irqreturn_t ras_error_interrupt(int irq, void *dev_id);
···
 	spin_lock(&ras_log_buf_lock);
 
 	status = rtas_call(ras_check_exception_token, 6, 1, NULL,
-			   RAS_VECTOR_OFFSET,
+			   RTAS_VECTOR_EXTERNAL_INTERRUPT,
 			   irq_map[irq].hwirq,
 			   RTAS_EPOW_WARNING | RTAS_POWERMGM_EVENTS,
 			   critical, __pa(&ras_log_buf),
···
 	spin_lock(&ras_log_buf_lock);
 
 	status = rtas_call(ras_check_exception_token, 6, 1, NULL,
-			   RAS_VECTOR_OFFSET,
+			   RTAS_VECTOR_EXTERNAL_INTERRUPT,
 			   irq_map[irq].hwirq,
 			   RTAS_INTERNAL_ERROR, 1 /*Time Critical */,
 			   __pa(&ras_log_buf),