9p: Small cleanup in <net/9p/9p.h>

There are two small cleanups in this patch:
 - p9_errstr2errno was declared twice - remove one declaration.
 - A uint8_t type was mixed in, change it to u8 to match
with the rest of the type names and remove dependency.

Cc: Eric Van Hensbergen <ericvh@gmail.com>
Cc: Ron Minnich <rminnich@sandia.gov>
Cc: Latchesar Ionkov <lucho@ionkov.net>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: Sasha Levin <levinsasha928@gmail.com>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>

include/net/9p/9p.h

@@ -714,7 +714,7 @@ struct p9_fcall {
 	size_t pbuf_size;
 	void *private;
 
-	uint8_t *sdata;
+	u8 *sdata;
 };
 
 struct p9_idpool;
@@ -728,7 +728,6 @@ void p9_idpool_put(int id, struct p9_idpool *p);
 int p9_idpool_check(int id, struct p9_idpool *p);
 
 int p9_error_init(void);
-int p9_errstr2errno(char *, int);
 int p9_trans_fd_init(void);
 void p9_trans_fd_exit(void);
 #endif /* NET_9P_H */