Disable SERIAL_FC for ARM_IOTSS_BEID, ARM_MPS2 family

Looks like listed boards have SERIAL_FC feature enabled, but does not provide pins definition for `PinMap_UART_CTS`, `PinMap_UART_RTS`.

This should fix the following failures:
ARM_IOTSS_BEID
ARM_MPS2_M0
ARM_MPS2_M3
ARM_MPS2_M4
ARM_MPS2_M7
[Error] serial_api.c@402,12: use of undeclared identifier 'PinMap_UART_RTS'

Author: mprse

targets/targets.json

@@ -5142,7 +5142,6 @@
             "PORTINOUT",
             "PORTOUT",
             "SERIAL",
-            "SERIAL_FC",
             "TSC"
         ]
     },
@@ -5191,7 +5190,6 @@
             "PORTINOUT",
             "PORTOUT",
             "SERIAL",
-            "SERIAL_FC",
             "TSC",
             "USTICKER"
         ],
@@ -5216,7 +5214,6 @@
             "PORTINOUT",
             "PORTOUT",
             "SERIAL",
-            "SERIAL_FC",
             "TSC",
             "MPU",
             "USTICKER"
@@ -5242,7 +5239,6 @@
             "PORTINOUT",
             "PORTOUT",
             "SERIAL",
-            "SERIAL_FC",
             "TSC",
             "MPU",
             "USTICKER"
@@ -5268,7 +5264,6 @@
             "PORTINOUT",
             "PORTOUT",
             "SERIAL",
-            "SERIAL_FC",
             "TSC",
             "MPU",
             "USTICKER"
@@ -5313,7 +5308,6 @@
             "PORTINOUT",
             "PORTOUT",
             "SERIAL",
-            "SERIAL_FC",
             "TSC",
             "MPU"
         ],