perf timechart: Refactor svg_build_topology_map()

Exchange the parameters of svg_build_topology_map() with 'struct
perf_env *env' and adjust the function accordingly.

This patch should not change any behavior, it is merely refactoring for
the following patch.

Committer notes:

No need to include env.h from svghelper.h, all it needs is a forward
declaration for 'struct perf_env', so move the include directive to
svghelper.c, where it is really needed.

Signed-off-by: Kyle Meyer <kyle.meyer@hpe.com>
Reviewed-by: Jiri Olsa <jolsa@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Russ Anderson <russ.anderson@hpe.com>
Link: http://lore.kernel.org/lkml/20190827214352.94272-2-meyerk@stormcage.eag.rdlabs.hpecorp.net
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>