basic fsh prototype (no comments yet)

@@ -243,10 +243,12 @@
         filio.h                 \
         flock.h                 \
         flock_impl.h            \
         fork.h                  \
         fsd.h                   \
+        fsh.h                   \
+        fsh_impl.h              \
         fss.h                   \
         fsspriocntl.h           \
         fsid.h                  \
         fssnap.h                \
         fssnap_if.h             \