fsmonitor: relocate socket file if .git directory is remote

If the .git directory is on a remote filesystem, create the socket
file in 'fsmonitor.socketDir' if it is defined, else create it in $HOME.

Signed-off-by: Eric DeCosta <edecosta@mathworks.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

fsmonitor-ipc.h

@@ -3,6 +3,8 @@
 
 #include "simple-ipc.h"
 
+struct repository;
+
 /*
  * Returns true if built-in file system monitor daemon is defined
  * for this platform.
@@ -16,7 +18,7 @@ int fsmonitor_ipc__is_supported(void);
  *
  * Returns NULL if the daemon is not supported on this platform.
  */
-const char *fsmonitor_ipc__get_path(void);
+const char *fsmonitor_ipc__get_path(struct repository *r);
 
 /*
  * Try to determine whether there is a `git-fsmonitor--daemon` process