newlib: link ESP8684 ROM symbols _printf_float & _scanf_float

components/esp_rom/esp32c2/ld/esp32c2.rom.newlib-nano.ld

@@ -40,8 +40,8 @@ vprintf = 0x400006b8;
 viprintf = 0x400006bc;
 vsnprintf = 0x400006c0;
 vsniprintf = 0x400006c4;
-__rom_printf_float = 0x400006c8;
-__rom_scanf_float = 0x400006cc;
+_printf_float = 0x400006c8;
+_scanf_float = 0x400006cc;
 _scanf_i = 0x400006d0;
 _scanf_chars = 0x400006d4;
 sscanf = 0x400006d8;