Fix I2C clock select.

Src/board.c

@@ -96,8 +96,8 @@ void SystemClock_Config(void)
   SystemCoreClock = 24000000;
 
   /* SetI2CClockSource */
-  RCC->CCIPR &= ~(((RCC_CCIPR_I2C1SEL << 16U) | RCC_CCIPR_I2C1SEL_1) >> 16U);
-  RCC->CCIPR |= (((RCC_CCIPR_I2C1SEL << 16U) | RCC_CCIPR_I2C1SEL_1) & 0x0000FFFFU);
+  RCC->CCIPR &= ~(RCC_CCIPR_I2C1SEL);
+  RCC->CCIPR |= RCC_CCIPR_I2C1SEL_1;
 }
 
 /**