selftests/bpf: Temporarily disable part of btf_dump:var_data test.

Commit 7443b296 ("x86/percpu: Move cpu_number next to current_task")
moved global per_cpu variable 'cpu_number' into pcpu_hot structure.
Therefore this part of var_data test is no longer valid.
Disable it until better solution is found.
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>

tools/testing/selftests/bpf/prog_tests/btf_dump.c

@@ -801,7 +801,7 @@ static void test_btf_dump_struct_data(struct btf *btf, struct btf_dump *d,
 static void test_btf_dump_var_data(struct btf *btf, struct btf_dump *d,
 				   char *str)
 {
-#if defined(__i386__) || defined(__x86_64__) || defined(__aarch64__)
+#if 0
 	TEST_BTF_DUMP_VAR(btf, d, NULL, str, "cpu_number", int, BTF_F_COMPACT,
 			  "int cpu_number = (int)100", 100);
 #endif