util/disk_cache: Add NONE type

Add an explicit enum for the DISK_CACHE_NONE type so that we don't
confuse with the MULTI_FILE case on android when the blob-cache is
used.

Signed-off-by: Rob Clark <robdclark@chromium.org>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/22248>

src/util/disk_cache.c

@@ -121,6 +121,7 @@ disk_cache_type_create(const char *gpu_name,
 
    /* Assume failure. */
    cache->path_init_failed = true;
+   cache->type = DISK_CACHE_NONE;
 
 #ifdef ANDROID
    /* Android needs the "disk cache" to be enabled for

src/util/disk_cache_os.h

@@ -50,6 +50,7 @@ extern "C" {
 #define CACHE_INDEX_MAX_KEYS (1 << CACHE_INDEX_KEY_BITS)
 
 enum disk_cache_type {
+   DISK_CACHE_NONE,
    DISK_CACHE_MULTI_FILE,
    DISK_CACHE_SINGLE_FILE,
    DISK_CACHE_DATABASE,