Move CH3-specific MPID_Win members into CH3

Several fields of MPID_Win were not used above the ADI.  These have been
moved to CH3 to reduce clutter.  Downstream devices should redefine
these fields in MPID_DEV_WIN_DECL if they are needed.

Reviewer: balaji

src/include/mpiimpl.h

@@ -1693,10 +1693,7 @@ typedef struct MPID_Win {
     MPI_Aint    size;        
     int          disp_unit;      /* Displacement unit of *local* window */
     MPID_Attribute *attributes;
-    MPID_Group *start_group_ptr; /* group passed in MPI_Win_start */
     MPID_Comm *comm_ptr;         /* Pointer to comm of window (dup) */
-    int         myrank;          /* Rank of this process in comm (used to 
-				    detect operations on self) */
 #ifdef USE_THREADED_WINDOW_CODE
     /* These were causing compilation errors.  We need to figure out how to
        integrate threads into MPICH before including these fields. */

src/mpid/ch3/include/mpidpre.h

@@ -257,6 +257,8 @@ struct MPIDI_Win_target_state {
 };
 
 #define MPIDI_DEV_WIN_DECL                                               \
+    int myrank;            /* Rank of this process in comm (used to      \
+                              detect operations on self) */              \
     volatile int my_counter;  /* completion counter for operations       \
                                  targeting this window */                \
     void **base_addrs;     /* array of base addresses of the windows of  \
@@ -293,6 +295,7 @@ struct MPIDI_Win_target_state {
                            this state must be updated collectively (in   \
                            fence) to ensure that the fence state across  \
                            all processes remains consistent. */          \
+    MPID_Group *start_group_ptr; /* group passed in MPI_Win_start */     \
     int start_assert;   /* assert passed to MPI_Win_start */             \
 
 #ifdef MPIDI_CH3_WIN_DECL