add I2C pins name to Arch and Arch Pro

Author: xiongyihui

libraries/mbed/targets/hal/TARGET_NXP/TARGET_LPC11UXX/TARGET_LPC11U24_401/PinNames.h

@@ -151,13 +151,19 @@ typedef enum {
     D12 = P0_8,
     D13 = P1_29, // P0_9 for Arch V1.0
 
+    D14 = P0_5,
+    D15 = P0_4,
+
     A0 = P0_11,
     A1 = P0_12,
     A2 = P0_13,
     A3 = P0_14,
     A4 = P0_16,
     A5 = P0_22,
 
+    I2C_SCL = D15,
+    I2C_SDA = D14,
+
     // Not connected
     NC = (int)0xFFFFFFFF,
 } PinName;

libraries/mbed/targets/hal/TARGET_NXP/TARGET_LPC176X/TARGET_MBED_LPC1768/PinNames.h

@@ -106,6 +106,9 @@ typedef enum {
     A4 = P1_30,
     A5 = P1_31,
 
+    I2C_SCL = D15,
+    I2C_SDA = D14,
+
     // Not connected
     NC = (int)0xFFFFFFFF
 } PinName;