perf tools: Shorten sample symbol resolving function signature

perf tools: Shorten sample symbol resolving function signature

Since two of the parameters come from the same 'struct
addr_location', rename machine__resolve_bstack() to sample__resolve_bstack()
and pass the that addr_location instead.

This is also for consistency with the same change that resulted in the
sample__resolve_mem() function.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-99ecqt8jiyyksiyx3se7l5ia@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>