bpf, cgroup: Remove unused exports

Except for a few of the networking hooks called from modular ipv4
or ipv6 code, all of hooks are just called from guaranteed to be
built-in code.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrey Ignatov <rdna@fb.com>
Link: https://lore.kernel.org/bpf/20200424064338.538313-2-hch@lst.de

Author: Christoph Hellwig

kernel/bpf/cgroup.c

@@ -1054,7 +1054,6 @@ int __cgroup_bpf_check_dev_permission(short dev_type, u32 major, u32 minor,
 
 	return !allow;
 }
-EXPORT_SYMBOL(__cgroup_bpf_check_dev_permission);
 
 static const struct bpf_func_proto *
 cgroup_base_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
@@ -1207,7 +1206,6 @@ int __cgroup_bpf_run_filter_sysctl(struct ctl_table_header *head,
 
 	return ret == 1 ? 0 : -EPERM;
 }
-EXPORT_SYMBOL(__cgroup_bpf_run_filter_sysctl);
 
 #ifdef CONFIG_NET
 static bool __cgroup_bpf_prog_array_is_empty(struct cgroup *cgrp,
@@ -1312,7 +1310,6 @@ int __cgroup_bpf_run_filter_setsockopt(struct sock *sk, int *level,
 		sockopt_free_buf(&ctx);
 	return ret;
 }
-EXPORT_SYMBOL(__cgroup_bpf_run_filter_setsockopt);
 
 int __cgroup_bpf_run_filter_getsockopt(struct sock *sk, int level,
 				       int optname, char __user *optval,
@@ -1399,7 +1396,6 @@ int __cgroup_bpf_run_filter_getsockopt(struct sock *sk, int level,
 	sockopt_free_buf(&ctx);
 	return ret;
 }
-EXPORT_SYMBOL(__cgroup_bpf_run_filter_getsockopt);
 #endif
 
 static ssize_t sysctl_cpy_dir(const struct ctl_dir *dir, char **bufp,