[PATCH 4.9 56/61] netfilter: nf_conntrack_pptp: fix compilation warning with W=1 build

[Greg Kroah-Hartman]

From: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx>

commit 4946ea5c1237036155c3b3a24f049fd5f849f8f6 upstream.

>> include/linux/netfilter/nf_conntrack_pptp.h:13:20: warning: 'const' type qualifier on return type has no effect [-Wignored-qualifiers]
extern const char *const pptp_msg_name(u_int16_t msg);
^~~~~~

Reported-by: kbuild test robot <lkp@xxxxxxxxx>
Fixes: 4c559f15efcc ("netfilter: nf_conntrack_pptp: prevent buffer overflows in debug code")
Signed-off-by: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 include/linux/netfilter/nf_conntrack_pptp.h |    2 +-
 net/netfilter/nf_conntrack_pptp.c           |    2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

--- a/include/linux/netfilter/nf_conntrack_pptp.h
+++ b/include/linux/netfilter/nf_conntrack_pptp.h
@@ -4,7 +4,7 @@
 
 #include <linux/netfilter/nf_conntrack_common.h>
 
-extern const char *const pptp_msg_name(u_int16_t msg);
+const char *pptp_msg_name(u_int16_t msg);
 
 /* state of the control session */
 enum pptp_ctrlsess_state {
--- a/net/netfilter/nf_conntrack_pptp.c
+++ b/net/netfilter/nf_conntrack_pptp.c
@@ -90,7 +90,7 @@ static const char *const pptp_msg_name_a
 	[PPTP_SET_LINK_INFO]		= "SET_LINK_INFO"
 };
 
-const char *const pptp_msg_name(u_int16_t msg)
+const char *pptp_msg_name(u_int16_t msg)
 {
 	if (msg > PPTP_MSG_MAX)
 		return pptp_msg_name_array[0];