Hi, @grosdode
An apology for the confusion I notice that there is a new version where this issue is fixed. Rev C can run PLL up to 150MHz.
Please use the SDK version 2.6.1, there is a new function that let you to init the PLL to 150MHz, also it solves the note (or SW errata) about the Rev C, you just need to change the function BOARD_InitBootClocks(); to now use BOARD_BootClockPLL150M();

This should work also for Rev D.
Rev B is still limited to 96MHz
Hope it helps you.