util/fossilize_db: Fix compile error with clang
../src/util/fossilize_db.c:178:58: error: use of GNU empty initializer extension [-Werror,-Wgnu-empty-initializer] char hash_str[FOSSILIZE_BLOB_HASH_LENGTH + 1] = {};
Fixes: eca6bb95 ("util/fossilize_db: add basic fossilize db util to read/write shader caches") Signed-off-by: Rob Clark robdclark@chromium.org