Made lwip memory configuration more specific for NXP targets

[mikaleppanen]

Description

There is a configuration problem with UBLOX_C027 cellular because of missing
LWIP memory configuration for the target.

Added configuration for LPC1768, LPC4088, LPC4088_DM targets and changed
NXP to more specific LPC546XX.

Pull request type

[X] Fix
[ ] Refactor
[ ] New target
[ ] Feature
[ ] Breaking change

[mikaleppanen]

@kjbracey-arm Please review.

[adbridge]

/morph build

[mbed-ci]

Build : SUCCESS

Build number : 2151
Build artifacts/logs : http://mbed-os.s3-website-eu-west-1.amazonaws.com/?prefix=builds/7019/

Triggering tests

/morph test
/morph uvisor-test
/morph export-build
/morph mbed2-build

[mbed-ci]

Test : SUCCESS

Build number : 1944
Test logs :http://mbed-os-logs.s3-website-us-west-1.amazonaws.com/?prefix=logs/7019/1944

[mbed-ci]

Exporter Build : SUCCESS

Build number : 1781
Build artifacts/logs : http://mbed-os.s3-website-eu-west-1.amazonaws.com/?prefix=builds/exporter/7019/