schedrelease() syscall for more efficient spinning

kernel/syscall/sched.c

@@ -0,0 +1,17 @@
+#include <stdint.h>
+#include "syscall.h"
+#include "sched.h"
+#include "proc/proc.h"
+#include "spinlock/spinlock.h"
+#include "errors.h"
+#include "hal/hal.h"
+
+int32_t SYSCALL0(sys_schedrelease) {
+  spinlock_acquire(&PROCS.spinlock);
+  Proc *proc = PROCS.current;
+  spinlock_release(&PROCS.spinlock);
+
+  proc_sched((void *)INTR_CURRENT_FRAME);
+
+  return E_OK;
+}