[PATCH] v9fs: handle kthread_create failure, minor bugfixes

- remove unnecessary -ENOMEM assignments
- return correct value when buf_check_size for second time in a buffer
- handle failures when create_workqueue and kthread_create are called
- use kzalloc instead of kmalloc/memset 0
- v9fs_str_copy and v9fs_str_compare were buggy, were used only in one
  place, correct the logic and move it to the place it is used.

Signed-off-by: Latchesar Ionkov <lucho@ionkov.net>
Cc: Eric Van Hensbergen <ericvh@ericvh.myip.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

fs/9p/error.h

@@ -176,4 +176,3 @@ static struct errormap errmap[] = {
 };
 
 extern int v9fs_error_init(void);
-extern int v9fs_errstr2errno(char *errstr, int len);