M467: I2C: Fix potential role switch failure

Fix in i2c_do_trsn(), interrupt doesn't change back to enabled due to premature return.

Author: ccli8

targets/TARGET_NUVOTON/TARGET_M460/i2c_api.c

@@ -444,13 +444,13 @@ static int i2c_do_trsn(i2c_t *obj, uint32_t i2c_ctl, int sync)
         case 0x08:  // Start
         case 0x10:  // Master Repeat Start
             if (i2c_ctl & I2C_CTL0_STA_Msk) {
-                return 0;
+                goto cleanup;
             } else {
                 break;
             }
         case 0xF8:  // Bus Released
             if ((i2c_ctl & (I2C_CTL0_STA_Msk | I2C_CTL0_STO_Msk)) == I2C_CTL0_STO_Msk) {
-                return 0;
+                goto cleanup;
             } else {
                 break;
             }
@@ -461,6 +461,8 @@ static int i2c_do_trsn(i2c_t *obj, uint32_t i2c_ctl, int sync)
         }
     }
 
+cleanup:
+
     i2c_enable_int(obj);
 
     return err;