perf maps: Re-use __maps__free_maps_by_name()

perf maps: Re-use __maps__free_maps_by_name()

maps__merge_in() hard codes the steps to free the maps_by_name list. It
seems to not map__put() each element before freeing, and it sets
maps_by_name_sorted to true after freeing, which may be harmless but
is inconsistent with maps__init() and other functions.

maps__maps_by_name_addr() is also quite hard to read because we already
have maps__maps_by_name() and maps__maps_by_address(), but the function
is only used in that place so delete it.

Reviewed-by: Ian Rogers <irogers@google.com>
Signed-off-by: James Clark <james.clark@arm.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20240507141210.195939-3-james.clark@arm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>