FF_LPC546XX: Remove LWIP feature
FF_LPC546XX: Remove LWIP feature

Signed-off-by: Mahadevan Mahesh <778f93d13cb34f99fc4522dcbb13a8dffe2c8547@nxp.com>

ryankurte/mbed-os,c1728p9/mbed-os,andcor02/mbed-os,ryankurte/mbed-os,karsev/mbed-os,mbedmicro/mbed,c1728p9/mbed-os,Archcady/mbed-os,c1728p9/mbed-os,Archcady/mbed-os,ryankurte/mbed-os,Archcady/mbed-os,ryankurte/mbed-os,mazimkhan/mbed-os,andcor02/mbed-os,karsev/mbed-os,betzw/mbed-os,kjbracey-arm/mbed,betzw/mbed-os,CalSol/mbed,Archcady/mbed-os,Archcady/mbed-os,ryankurte/mbed-os,CalSol/mbed,karsev/mbed-os,mazimkhan/mbed-os,mazimkhan/mbed-os,karsev/mbed-os,andcor02/mbed-os,kjbracey-arm/mbed,Archcady/mbed-os,c1728p9/mbed-os,mbedmicro/mbed,mbedmicro/mbed,mbedmicro/mbed,karsev/mbed-os,mbedmicro/mbed,CalSol/mbed,c1728p9/mbed-os,CalSol/mbed,mazimkhan/mbed-os,betzw/mbed-os,andcor02/mbed-os,karsev/mbed-os,c1728p9/mbed-os,kjbracey-arm/mbed,mazimkhan/mbed-os,CalSol/mbed,betzw/mbed-os,ryankurte/mbed-os,kjbracey-arm/mbed,betzw/mbed-os,CalSol/mbed,betzw/mbed-os,andcor02/mbed-os,mazimkhan/mbed-os,andcor02/mbed-os