Move bootstage timer out of lib/time.c

The standalone example does not have get_timer() defined, so we cannot
rely on it being available.

Move the timer function into boootstage.c to avoid this problem.

This corrects a build breakage for the standalone example on some boards.

Signed-off-by: Simon Glass <sjg@chromium.org>
Acked-by: Matthias Fuchs <matthias.fuchs@esd.eu>
diff --git a/common/bootstage.c b/common/bootstage.c
index d2bbe63..4e01d92 100644
--- a/common/bootstage.c
+++ b/common/bootstage.c
@@ -156,3 +156,20 @@
 			"- please increase CONFIG_BOOTSTAGE_USER_COUNT\n",
 		       next_id - BOOTSTAGE_ID_COUNT);
 }
+
+ulong __timer_get_boot_us(void)
+{
+	static ulong base_time;
+
+	/*
+	 * We can't implement this properly. Return 0 on the first call and
+	 * larger values after that.
+	 */
+	if (base_time)
+		return get_timer(base_time) * 1000;
+	base_time = get_timer(0);
+	return 0;
+}
+
+ulong timer_get_boot_us(void)
+	__attribute__((weak, alias("__timer_get_boot_us")));
diff --git a/include/bootstage.h b/include/bootstage.h
index 06ab2c8..a000538 100644
--- a/include/bootstage.h
+++ b/include/bootstage.h
@@ -204,6 +204,13 @@
 };
 
 /*
+ * Return the time since boot in microseconds, This is needed for bootstage
+ * and should be defined in CPU- or board-specific code. If undefined then
+ * millisecond resolution will be used (the standard get_timer()).
+ */
+ulong timer_get_boot_us(void);
+
+/*
  * Board code can implement show_boot_progress() if needed.
  *
  * @param val	Progress state (enum bootstage_id), or -id if an error
diff --git a/include/common.h b/include/common.h
index 74d9704..4b5841e 100644
--- a/include/common.h
+++ b/include/common.h
@@ -207,13 +207,6 @@
 #endif /* CONFIG_SERIAL_MULTI */
 
 /*
- * Return the time since boot in microseconds, This is needed for bootstage
- * and should be defined in CPU- or board-specific code. If undefined then
- * millisecond resolution will be used (the standard get_timer()).
- */
-ulong timer_get_boot_us(void);
-
-/*
  * General Purpose Utilities
  */
 #define min(X, Y)				\
diff --git a/lib/time.c b/lib/time.c
index 69edc3d..6e2937b 100644
--- a/lib/time.c
+++ b/lib/time.c
@@ -47,20 +47,3 @@
 	while (msec--)
 		udelay(1000);
 }
-
-ulong __timer_get_boot_us(void)
-{
-	static ulong base_time;
-
-	/*
-	 * We can't implement this properly. Return 0 on the first call and
-	 * larger values after that.
-	 */
-	if (base_time)
-		return get_timer(base_time) * 1000;
-	base_time = get_timer(0);
-	return 0;
-}
-
-ulong timer_get_boot_us(void)
-	__attribute__((weak, alias("__timer_get_boot_us")));