Revert "perf dso: Add missed dso__put to dso__load_kcore"

This reverts commit e5de9ea779.

The patch introduced `map__zput(new_node->map)` in the kcore load
path, causing a segmentation fault when running `perf c2c report`.

The issue arises because `maps__merge_in` directly modifies and
inserts the caller's `new_map`, causing it to be freed prematurely
while still referenced by kmaps.

Later branchs (6.12, 6.15, 6.16) are not affected because they use
a different merge approach with a lazily sorted array, which avoids
modifying the original `new_map`.

Fixes: e5de9ea779 ("perf dso: Add missed dso__put to dso__load_kcore")

Signed-off-by: jingxian.li <jingxian.li@shopee.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

tools/perf/util/symbol.c

@@ -1366,7 +1366,6 @@ static int dso__load_kcore(struct dso *dso, struct map *map,
 				goto out_err;
 			}
 		}
-		map__zput(new_node->map);
 		free(new_node);
 	}