[netX10/51] Drv_Led: Linking fails if function level linking is disabled (unresolved reference to HifPio driver)

Linking to netX10/51 lib failed if function level (-gc-sections) linking is disabled.
Linker returns unresolved reference to HifPio driver:
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librcx_netx51.a(Drv_Led.o): In function `drvLedHifPioInitializeLed':
Drv_Led.c:444: undefined reference to `Drv_HifPioIdentifyHifPio'
Drv_Led.c:444: undefined reference to `Drv_HifPioInitializeHifPio'
librcx_netx51.a(Drv_Led.o): In function `drvLedHifPioSetLed':
Drv_Led.c:507: undefined reference to `Drv_HifPioGetOutputs'
Drv_Led.c:507: undefined reference to `Drv_HifPioSetOutputs'
librcx_netx51.a(Drv_Led.o): In function `drvLedHifPioClearLed':
Drv_Led.c:570: undefined reference to `Drv_HifPioGetOutputs'
Drv_Led.c:570: undefined reference to `Drv_HifPioSetOutputs'
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HifPio driver is not available for netX10/51. However, hifpio driver is offered as lowlevel driver to the LED driver regardless of the used chip type.