perf test vmlinux-kallsyms: Ignore aliases to _etext when searching on kallsyms

No need to search for aliases for the symbol that marks the end of the
kernel text segment, the following patch will make such symbols not to
be found when searching in the kallsyms maps causing this test to fail.

So as a prep patch to avoid breaking bisection, ignore such symbols.
Tested-by: Jiri Olsa <jolsa@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Song Liu <songliubraving@fb.com>
Cc: Stanislav Fomichev <sdf@google.com>
Cc: Thomas Richter <tmricht@linux.ibm.com>
Link: https://lkml.kernel.org/n/tip-qfwuih8cvmk9doh7k5k244eq@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/tests/vmlinux-kallsyms.c

@@ -161,9 +161,16 @@ int test__vmlinux_matches_kallsyms(struct test *test __maybe_unused, int subtest
 
 				continue;
 			}
-		} else
+		} else if (mem_start == kallsyms.vmlinux_map->end) {
+			/*
+			 * Ignore aliases to _etext, i.e. to the end of the kernel text area,
+			 * such as __indirect_thunk_end.
+			 */
+			continue;
+		} else {
 			pr_debug("ERR : %#" PRIx64 ": %s not on kallsyms\n",
 				 mem_start, sym->name);
+		}
 
 		err = -1;
 	}