perf test: Ignore kcore files in the "vmlinux matches kallsyms" test

perf test: Ignore kcore files in the "vmlinux matches kallsyms" test

Before:

  # perf test -v kallsyms
<SNIP>
  Maps only in vmlinux:
   ffffffff81d5e000-ffffffff81ec3ac8 115e000 [kernel].init.text
   ffffffff81ec3ac8-ffffffffa0000000 12c3ac8 [kernel].exit.text
   ffffffffa0000000-ffffffffa000c000 0 [fjes]
   ffffffffa000c000-ffffffffa0017000 0 [video]
   ffffffffa0017000-ffffffffa001c000 0 [grace]
<SNIP>
   ffffffffa0a7f000-ffffffffa0ba5000 0 [xfs]
   ffffffffa0ba5000-ffffffffffffffff 0 [veth]
  Maps in vmlinux with a different name in kallsyms:
  Maps only in kallsyms:
   ffff880000100000-ffff88001000b000 80000103000 [kernel.kallsyms]
   ffff88001000b000-ffff880100000000 8001000e000 [kernel.kallsyms]
   ffff880100000000-ffffc90000000000 80100003000 [kernel.kallsyms]
<SNIP>
   ffffffffa0000000-ffffffffff600000 7fffa0003000 [kernel.kallsyms]
   ffffffffff600000-ffffffffffffffff 7fffff603000 [kernel.kallsyms]
  test child finished with -1
  ---- end ----
  vmlinux symtab matches kallsyms: FAILED!
  #

After:

  # perf test -v 1
   1: vmlinux symtab matches kallsyms                          :
  --- start ---
  test child forked, pid 7058
  Looking at the vmlinux_path (8 entries long)
  Using /lib/modules/4.6.0-rc1+/build/vmlinux for symbols
  0xffffffff81076870: diff end addr for aesni_gcm_dec v: 0xffffffff810791f2 k: 0xffffffff81076902
  0xffffffff81079200: diff end addr for aesni_gcm_enc v: 0xffffffff8107bb03 k: 0xffffffff81079292
  0xffffffff8107e8d0: diff end addr for aesni_gcm_enc_avx_gen2 v: 0xffffffff81083e76 k: 0xffffffff8107e943
  0xffffffff81083e80: diff end addr for aesni_gcm_dec_avx_gen2 v: 0xffffffff81089611 k: 0xffffffff81083ef3
  0xffffffff81089990: diff end addr for aesni_gcm_enc_avx_gen4 v: 0xffffffff8108e7c4 k: 0xffffffff81089a03
  0xffffffff8108e7d0: diff end addr for aesni_gcm_dec_avx_gen4 v: 0xffffffff810937ef k: 0xffffffff8108e843
  Maps only in vmlinux:
   ffffffff81d5e000-ffffffff81ec3ac8 115e000 [kernel].init.text
   ffffffff81ec3ac8-ffffffffa0000000 12c3ac8 [kernel].exit.text
  Maps in vmlinux with a different name in kallsyms:
  Maps only in kallsyms:
  test child finished with -1
  ---- end ----
 vmlinux symtab matches kallsyms: FAILED!
  #

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Fixes: 8e0cf965f95e ("perf symbols: Add support for reading from /proc/kcore")
Link: http://lkml.kernel.org/n/tip-n6vrwt9t89w8k769y349govx@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>