Favor stdint.h types in internal types
Use uint8_t for PSA buffers. Keep unsigned char for generic libc
buffers and for mbedtls buffers.
diff --git a/include/psa/crypto_struct.h b/include/psa/crypto_struct.h
index fdf78a8..0ddc7a3 100644
--- a/include/psa/crypto_struct.h
+++ b/include/psa/crypto_struct.h
@@ -210,7 +210,7 @@
* hence we must store it for the lifetime of the operation.
* This is different from HKDF, where the key is only used
* in the extraction phase, but not during expansion. */
- unsigned char *key;
+ uint8_t *key;
size_t key_len;
/* `A(i) + seed` in the notation of RFC 5246, Sect. 5 */