Added I2C stm32u5_support

Tested I2C master mode on 16MHz HSI

lib/stm32/u5/i2c.c

@@ -0,0 +1,31 @@
+/** @defgroup i2c_file I2C
+ *
+ * @ingroup STM32U5xx
+ *
+ * @brief <b>libopencm3 STM32U5xx I2C</b>
+ *
+ * @version 1.0.0
+ *
+ * @date 13 OCt 2024
+ *
+ * LGPL License Terms @ref lgpl_license
+ */
+
+/*
+ * This file is part of the libopencm3 project.
+ *
+ * This library is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this library.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <libopencm3/stm32/i2c.h>