Added initial BL61X and BL808 support, some chip changes

lib/chip/blisp_chip_bl61x.c

@@ -0,0 +1,11 @@
+// SPDX-License-Identifier: MIT
+#include "blisp.h"
+
+struct blisp_chip blisp_chip_bl61x = {
+    .type = BLISP_CHIP_BL61X,
+    .type_str = "bl808",
+    .usb_isp_available = true,
+    .default_xtal = "-", // ?
+    .handshake_byte_multiplier = 0.003f,
+    .needs_eflash_loader = false
+};