util/disk_cache: hash pointer size and gpu name into cache keys

This allows to get rid of the arch and gpu name directories.

v2: (Timothy Arceri) don't use an opaque data type to store
    pointer size and gpu name.

v3: (Timothy Arceri) use blob to store driver keys just make sure
    to store null terminator for strings, and make sure blob is
    defined by disk_cache and not it's users.

v4: (Timothy Arceri) fix typo, and make ptr_size a uint8_t.

Signed-off-by: Grazvydas Ignotas <notasas@gmail.com>
Reviewed-by: Nicolai Hähnle <nicolai.haehnle@amd.com>

src/util/disk_cache.h

@@ -43,23 +43,6 @@ typedef uint8_t cache_key[CACHE_KEY_SIZE];
 
 struct disk_cache;
 
-static inline const char *
-get_arch_bitness_str(void)
-{
-    if (sizeof(void *) == 4)
-#ifdef __ILP32__
-        return "ilp-32";
-#else
-        return "32";
-#endif
-    if (sizeof(void *) == 8)
-        return "64";
-
-    /* paranoia check which will be dropped by the optimiser */
-    assert(!"unknown_arch");
-    return "unknown_arch";
-}
-
 static inline bool
 disk_cache_get_function_timestamp(void *ptr, uint32_t* timestamp)
 {