selftests/bpf: Remove extern from kfuncs declarations

There's no need to keep the extern in kfuncs declarations.
Suggested-by: David Vernet <void@manifault.com>
Acked-by: David Vernet <void@manifault.com>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/r/20230515133756.1658301-10-jolsa@kernel.orgSigned-off-by: Alexei Starovoitov <ast@kernel.org>

tools/testing/selftests/bpf/bpf_testmod/bpf_testmod_kfunc.h

@@ -10,31 +10,31 @@
 #define __ksym
 #endif
 
-extern struct prog_test_ref_kfunc *
+struct prog_test_ref_kfunc *
 bpf_kfunc_call_test_acquire(unsigned long *scalar_ptr) __ksym;
-extern void bpf_kfunc_call_test_release(struct prog_test_ref_kfunc *p) __ksym;
+void bpf_kfunc_call_test_release(struct prog_test_ref_kfunc *p) __ksym;
 void bpf_kfunc_call_test_ref(struct prog_test_ref_kfunc *p) __ksym;
 
-extern void bpf_kfunc_call_test_mem_len_pass1(void *mem, int len) __ksym;
-extern int *bpf_kfunc_call_test_get_rdwr_mem(struct prog_test_ref_kfunc *p, const int rdwr_buf_size) __ksym;
-extern int *bpf_kfunc_call_test_get_rdonly_mem(struct prog_test_ref_kfunc *p, const int rdonly_buf_size) __ksym;
-extern int *bpf_kfunc_call_test_acq_rdonly_mem(struct prog_test_ref_kfunc *p, const int rdonly_buf_size) __ksym;
-extern void bpf_kfunc_call_int_mem_release(int *p) __ksym;
-extern u32 bpf_kfunc_call_test_static_unused_arg(u32 arg, u32 unused) __ksym;
+void bpf_kfunc_call_test_mem_len_pass1(void *mem, int len) __ksym;
+int *bpf_kfunc_call_test_get_rdwr_mem(struct prog_test_ref_kfunc *p, const int rdwr_buf_size) __ksym;
+int *bpf_kfunc_call_test_get_rdonly_mem(struct prog_test_ref_kfunc *p, const int rdonly_buf_size) __ksym;
+int *bpf_kfunc_call_test_acq_rdonly_mem(struct prog_test_ref_kfunc *p, const int rdonly_buf_size) __ksym;
+void bpf_kfunc_call_int_mem_release(int *p) __ksym;
+u32 bpf_kfunc_call_test_static_unused_arg(u32 arg, u32 unused) __ksym;
 
-extern void bpf_testmod_test_mod_kfunc(int i) __ksym;
+void bpf_testmod_test_mod_kfunc(int i) __ksym;
 
-extern __u64 bpf_kfunc_call_test1(struct sock *sk, __u32 a, __u64 b,
+__u64 bpf_kfunc_call_test1(struct sock *sk, __u32 a, __u64 b,
 				__u32 c, __u64 d) __ksym;
-extern int bpf_kfunc_call_test2(struct sock *sk, __u32 a, __u32 b) __ksym;
-extern struct sock *bpf_kfunc_call_test3(struct sock *sk) __ksym;
-extern long bpf_kfunc_call_test4(signed char a, short b, int c, long d) __ksym;
+int bpf_kfunc_call_test2(struct sock *sk, __u32 a, __u32 b) __ksym;
+struct sock *bpf_kfunc_call_test3(struct sock *sk) __ksym;
+long bpf_kfunc_call_test4(signed char a, short b, int c, long d) __ksym;
 
-extern void bpf_kfunc_call_test_pass_ctx(struct __sk_buff *skb) __ksym;
-extern void bpf_kfunc_call_test_pass1(struct prog_test_pass1 *p) __ksym;
-extern void bpf_kfunc_call_test_pass2(struct prog_test_pass2 *p) __ksym;
-extern void bpf_kfunc_call_test_mem_len_fail2(__u64 *mem, int len) __ksym;
+void bpf_kfunc_call_test_pass_ctx(struct __sk_buff *skb) __ksym;
+void bpf_kfunc_call_test_pass1(struct prog_test_pass1 *p) __ksym;
+void bpf_kfunc_call_test_pass2(struct prog_test_pass2 *p) __ksym;
+void bpf_kfunc_call_test_mem_len_fail2(__u64 *mem, int len) __ksym;
 
-extern void bpf_kfunc_call_test_destructive(void) __ksym;
+void bpf_kfunc_call_test_destructive(void) __ksym;
 
 #endif /* _BPF_TESTMOD_KFUNC_H */