Upcall: Process gfid sent as part of upcalls.

Made changes to pass gfid instead of inode from server translator
so that libgfapi client can map it to an inode and construct
glfs_object out of it which can be used by Ganesha server to invalidate
cache_entry.

Also created a list to store the gfids received & sent by various
protocol/client translors

Signed-off-by: Soumya Koduri <skoduri@redhat.com>