[2.7] bpo-31848: Fix broken error handling in Aifc_read.initfp() when the SSND chunk is not found (GH-5240)#5781

serhiy-storchaka merged 2 commits intopython:2.7python/cpython:2.7from

miss-islington:backport-80d20b9-2.7miss-islington/cpython:backport-80d20b9-2.7Copy head branch name to clipboard