DM: vrtc code cleanup

- Move the variable local_time from main.c to rtc.c
- Change vrtc_init to return int instead of pointer to vrtc. We do
  track vrtc in struct vmctx.

Signed-off-by: Yin Fengwei <fengwei.yin@intel.com>
Acked-by: Anthony Xu <anthony.xu@intel.com>

devicemodel/include/vmmapi.h

@@ -34,8 +34,6 @@
 #include "types.h"
 #include "vmm.h"
 
-#include "atkbdc.h"
-
 /*
  * API version for out-of-tree consumers for making compile time decisions.
  */
@@ -47,8 +45,6 @@
 #define ALIGN_UP(x, align)	(((x) + ((align)-1)) & ~((align)-1))
 #define ALIGN_DOWN(x, align)	((x) & ~((align)-1))
 
-struct iovec;
-
 struct vmctx {
 	int     fd;
 	int     vmid;
@@ -64,8 +60,8 @@ struct vmctx {
 	uuid_t	vm_uuid;
 
 	/* fields to track virtual devices */
-	struct atkbdc_base *atkbdc_base;
-	struct vrtc *vrtc;
+	void *atkbdc_base;
+	void *vrtc;
 };
 
 /*