blk-crypto: Simplify check for fallback support

Since blk-crypto-fallback supports all blk_crypto_keys except wrapped
keys, just check for that condition directly instead of using
__blk_crypto_cfg_supported().  With this done,
__blk_crypto_cfg_supported() is now used only for the hardware support.

Reviewed-by: Christoph Hellwig <[email protected]>
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Eric Biggers <[email protected]>

block/blk-crypto-fallback.c

@@ -496,8 +496,7 @@ bool blk_crypto_fallback_bio_prep(struct bio *bio)
 		return false;
 	}
 
-	if (!__blk_crypto_cfg_supported(blk_crypto_fallback_profile,
-					&bc->bc_key->crypto_cfg)) {
+	if (bc->bc_key->crypto_cfg.key_type != BLK_CRYPTO_KEY_TYPE_RAW) {
 		bio_endio_status(bio, BLK_STS_NOTSUPP);
 		return false;
 	}