kernel: pid_namespace: remove unused set_memfd_noexec_scope()

This inline function is unused, remove it.

Link: https://lkml.kernel.org/r/20230610102858.31488-1-yuehaibing@huawei.comSigned-off-by: YueHaibing <yuehaibing@huawei.com>
Cc: Jeff Xu <jeffxu@google.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Luis Chamberlain <mcgrof@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

kernel/pid_sysctl.h

@@ -52,7 +52,6 @@ static inline void register_pid_ns_sysctl_table_vm(void)
 }
 #else
 static inline void initialize_memfd_noexec_scope(struct pid_namespace *ns) {}
-static inline void set_memfd_noexec_scope(struct pid_namespace *ns) {}
 static inline void register_pid_ns_sysctl_table_vm(void) {}
 #endif