perf tools: Move some callchain parser functions to callchain.c

And rename record_callchain_parse() to parse_callchain_record_opt() in
accordance to parse_callchain_report_opt().

Signek-off-by: Namhyung Kim <namhyung@kernel.org>
perf tools: Introduce perf_callchain_config()

This patch adds support for following config options to ~/.perfconfig file.

  [call-graph]
    record-mode = dwarf
    dump-size = 8192
    print-type = fractal
    order = callee
    threshold = 0.5
    print-limit = 128
    sort-key = function

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
perf tools: Convert {record,top}.call-graph option to call-graph.record-mode

So that it'll be passed to perf_callchain_config().

Signed-off-by: Namhyung Kim <namhyung@kernel.org>