Add I2C example for M5Stack DigiClock (#18132)

tasmota/berry/drivers/M5Stack_DigiClock.be

@@ -0,0 +1,38 @@
+# Simple driver for M5Stack DigiClock I2C 7 segments LED
+#
+# https://docs.m5stack.com/en/unit/digi_clock
+
+class M5Stack_DigiClock
+  static var I2C_ADDR = 0x30                # default I2C address is 0x30
+  var led
+  var addr
+
+  def init(addr)
+    if !addr    addr = self.I2C_ADDR end
+
+    self.addr = addr
+    self.led = tasmota.wire_scan(addr)
+
+    if self.led == nil    raise "configuration_error", "Could not find DigiClock I2C device" end
+  end
+
+  def set_brightness(b)
+    if b < 0      b = 0 end
+    if b > 8      b = 8 end
+    self.led.write(self.addr, 0x30, b, 1)
+  end
+
+  def set_text(t)
+    self.led.write_bytes(0x30, 0x20, bytes().fromstring(str(t)))
+  end
+end
+
+return M5Stack_DigiClock
+
+#-
+
+var led = M5Stack_DigiClock()
+led.set_brightness(1)
+led.set_text("1234")
+
+-#