Add initial support for BL60X

lib/chip/blisp_chip_bl60x.c

@@ -0,0 +1,9 @@
+#include "blisp.h"
+
+struct blisp_chip blisp_chip_bl60x = {
+    .type = BLISP_CHIP_BL60X,
+    .type_str = "bl60x",
+    .usb_isp_available = false,
+    .default_eflash_loader_xtal = "40m",
+    .handshake_byte_multiplier = 0.006f,
+};

lib/chip/blisp_chip_bl70x.c

@@ -3,5 +3,7 @@
 struct blisp_chip blisp_chip_bl70x = {
     .type = BLISP_CHIP_BL70X,
     .type_str = "bl70x",
-    .usb_isp_available = true
+    .usb_isp_available = true,
+    .default_eflash_loader_xtal = "32m",
+    .handshake_byte_multiplier = 0.003f,
 };