add sched_{get,set}attr syscall numbers and SCHED_DEADLINE macro

linux 3.14 introduced sched_getattr and sched_setattr syscalls in
commit d50dde5a10f305253cbc3855307f608f8a3c5f73

and the related SCHED_DEADLINE scheduling policy in
commit aab03e05e8f7e26f51dee792beddcb5cca9215a5

but struct sched_attr "extended scheduling parameters data structure"
is not yet exported to userspace (necessary for using the syscalls)
so related uapi definitions are not added yet.

arch/microblaze/bits/syscall.h

@@ -375,6 +375,8 @@
 #define __NR_process_vm_writev 378
 #define __NR_kcmp 379
 #define __NR_finit_module 380
+#define __NR_sched_setattr 381
+#define __NR_sched_getattr 382
 
 /* Repeated with SYS_ prefix */
 
@@ -756,3 +758,5 @@
 #define SYS_process_vm_writev 378
 #define SYS_kcmp 379
 #define SYS_finit_module 380
+#define SYS_sched_setattr 381
+#define SYS_sched_getattr 382