Documentation/networking: fix default_ttl typo in mpls-sysctl

default_ttl should be integer instead of bool

Reported-by: Ying Xu <yinxu@redhat.com>
Fixes: a59166e470 ("mpls: allow TTL propagation from IP packets to be configured")
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Documentation/networking/mpls-sysctl.txt

@@ -30,7 +30,7 @@ ip_ttl_propagate - BOOL
 	0 - disabled / RFC 3443 [Short] Pipe Model
 	1 - enabled / RFC 3443 Uniform Model (default)
 
-default_ttl - BOOL
+default_ttl - INTEGER
 	Default TTL value to use for MPLS packets where it cannot be
 	propagated from an IP header, either because one isn't present
 	or ip_ttl_propagate has been disabled.