IB/hfi1: Keep SC_USER as the last send context type

SC_USER needs to be the last send context type to ensure other
send context types get their allocation when num_user_contexts
is set to a large number.

This fixes a panic when the module parameter num_user_contexts
is set to 141 and larger.
Reviewed-by: NDean Luick <dean.luick@intel.com>
Signed-off-by: NJianxin Xiong <jianxin.xiong@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

drivers/staging/rdma/hfi1/pio.h

@@ -49,10 +49,10 @@
 
 /* send context types */
 #define SC_KERNEL 0
-#define SC_ACK    1
-#define SC_USER   2
-#define SC_VL15   3
-#define SC_MAX    4
+#define SC_VL15   1
+#define SC_ACK    2
+#define SC_USER   3	/* must be the last one: it may take all left */
+#define SC_MAX    4	/* count of send context types */
 
 /* invalid send context index */
 #define INVALID_SCI 0xff