scoutfs: Tidy some enum usage

Prefer named to anonymous enums. This helps readability a little.

Use enum as param type if possible (a couple spots).

Remove unused enum in lock_server.c.

Define enum spbm_flags using shift notation for consistency.

Rename get_file_block()'s "gfb" parameter to "flags" for consistency.

Signed-off-by: Andy Grover <agrover@versity.com>

kmod/src/lock_server.c

@@ -118,12 +118,6 @@ struct server_lock_node {
 	struct list_head invalidated;
 };
 
-enum {
-	CLE_GRANTED,
-	CLE_REQUESTED,
-	CLE_INVALIDATED,
-};
-
 /*
  * Interactions with the client are tracked with these little mode
  * wrappers.