test: wdt: filter out test for lpc and RTxxx

[hakehuang]

nxp LPC and RTxxx series has a power firmware which is conflict with noninit variable, so filter out cases for those platforms

fixing: #48801

Signed-off-by: Hake Huang [email protected]

[dleach02]

To be clear on the problem, the test case for watchdog has a variable in the "noinit" section that the test case expects to retain its value across resets. For some of our platforms, there is sections of memory which can do this but there isn't a good way to force the noinit section to reside in these memory regions.