graphics/libheif: Update to 1.15.2

Backport upstream commits be16fc6767c8b3a2f6e78efdc9d2b6f07e3e558a and
4fd25823d16ccbe082ad3be9b96656296284d9b4

Changelog: https://github.com/strukturag/libheif/releases/tag/v1.15.2
References:
https://github.com/strukturag/libheif/commit/be16fc6767c8b3a2f6e78efdc9d2b6f07e3e558a
https://github.com/strukturag/libheif/commit/4fd25823d16ccbe082ad3be9b96656296284d9b4

Approved by: makc (implicit via private email)