Update interface of prif_sync_all based on latest design doc

choices.

Author: ktras

src/caffeine/synchronization_m.f90

@@ -1,13 +1,18 @@
 ! Copyright (c), The Regents of the University of California
 ! Terms of use are as specified in LICENSE.txt
 module synchronization_m
+    use iso_c_binding, only: c_int
     implicit none
     private
     public :: prif_sync_all
 
     interface
 
-      module subroutine prif_sync_all()
+      module subroutine prif_sync_all(stat, errmsg, errmsg_alloc)
+        implicit none
+        integer(c_int), intent(out), optional :: stat
+        character(len=*), intent(inout), optional :: errmsg
+        character(len=:), intent(inout), allocatable, optional :: errmsg_alloc
       end subroutine
 
     end interface

src/caffeine/synchronization_s.f90

@@ -8,6 +8,7 @@
 
   module procedure prif_sync_all
 
+    !TODO: handle optional args stat, errmsg, errmsg_alloc
     call caf_sync_all
 
   end procedure