factor out priorities for workqueue.h and sched.h

From: Clark Williams <williams@redhat.com>

This fixes a circular dependency between sched.h and workqueue.h by factoring out the common
defines to a new header which is included by both

Signed-off-by: Clark Williams <williams@redhat.com>
---

 include/linux/sched.h      |   19 +------------------
 include/linux/sched_prio.h |   23 +++++++++++++++++++++++
 include/linux/workqueue.h  |    1 +
 3 files changed, 25 insertions(+), 18 deletions(-)

diff --git a/include/linux/sched.h b/include/linux/sched.h
index 42deb55..b7ab7ca 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -1428,24 +1428,7 @@ struct task_struct {
 # define set_printk_might_sleep(x) do { } while(0)
 #endif
 
-/*
- * Priority of a process goes from 0..MAX_PRIO-1, valid RT
- * priority is 0..MAX_RT_PRIO-1, and SCHED_NORMAL/SCHED_BATCH
- * tasks are in the range MAX_RT_PRIO..MAX_PRIO-1. Priority
- * values are inverted: lower p->prio value means higher priority.
- *
- * The MAX_USER_RT_PRIO value allows the actual maximum
- * RT priority to be separate from the value exported to
- * user-space.  This allows kernel threads to set their
- * priority to a value higher than any user task. Note:
- * MAX_RT_PRIO must not be smaller than MAX_USER_RT_PRIO.
- */
-
-#define MAX_USER_RT_PRIO	100
-#define MAX_RT_PRIO		MAX_USER_RT_PRIO
-
-#define MAX_PRIO		(MAX_RT_PRIO + 40)
-#define DEFAULT_PRIO		(MAX_RT_PRIO + 20)
+#include <linux/sched_prio.h>
 
 static inline int rt_prio(int prio)
 {
diff --git a/include/linux/sched_prio.h b/include/linux/sched_prio.h
new file mode 100644
index 0000000..ec5114a
--- /dev/null
+++ b/include/linux/sched_prio.h
@@ -0,0 +1,23 @@
+#ifndef __SCHED_PRIO_H
+#define __SCHED_PRIO_H
+
+/*
+ * Priority of a process goes from 0..MAX_PRIO-1, valid RT
+ * priority is 0..MAX_RT_PRIO-1, and SCHED_NORMAL/SCHED_BATCH
+ * tasks are in the range MAX_RT_PRIO..MAX_PRIO-1. Priority
+ * values are inverted: lower p->prio value means higher priority.
+ *
+ * The MAX_USER_RT_PRIO value allows the actual maximum
+ * RT priority to be separate from the value exported to
+ * user-space.  This allows kernel threads to set their
+ * priority to a value higher than any user task. Note:
+ * MAX_RT_PRIO must not be smaller than MAX_USER_RT_PRIO.
+ */
+
+#define MAX_USER_RT_PRIO	100
+#define MAX_RT_PRIO		MAX_USER_RT_PRIO
+
+#define MAX_PRIO		(MAX_RT_PRIO + 40)
+#define DEFAULT_PRIO		(MAX_RT_PRIO + 20)
+
+#endif
diff --git a/include/linux/workqueue.h b/include/linux/workqueue.h
index fbcbec6..4ea6292 100644
--- a/include/linux/workqueue.h
+++ b/include/linux/workqueue.h
@@ -9,6 +9,7 @@
 #include <linux/linkage.h>
 #include <linux/bitops.h>
 #include <linux/plist.h>
+#include <linux/sched_prio.h>
 #include <asm/atomic.h>
 
 struct workqueue_struct;