fixed code structure regarding clock and timer interfaces (#106)

Author: frogrammer9

src/example_sbi/CMakeLists.txt

@@ -1,6 +1,7 @@
-#include <hal/timer.h>
-#include <hal/trap.h>
-#include <stdbigos/clock.h>
+#include "clock.h"
+
+#include <hal/include/timer.h>
+#include <hal/include/trap.h>
 
 static u64 g_tick_quantum;
 static u64 g_next_deadline;

src/example_sbi/entry.c

@@ -1,8 +1,8 @@
 #ifndef STDBIGOS_CLOCK
 #define STDBIGOS_CLOCK
 
-#include "error.h"
-#include "types.h"
+#include "stdbigos/error.h"
+#include "stdbigos/types.h"
 
 /**
  * @file include/stdbigos/clock.h

src/lib/stdbigos/clock.c src/kernel/clock/clock.csrc/lib/stdbigos/clock.c renamed to src/kernel/clock/clock.c

@@ -1,4 +1,4 @@
-#include <hal/timer.h>
+#include <hal/include/timer.h>
 #include <stdbigos/sbi.h>
 #include <stdbigos/sbi_utils.h>