fpga frequency set via configuration file

[coolbreeze413]

• appfpga binary should contain the C16 and C21 frequency settings as well
• tool should have a way to specify the frequencies, through a configuration file
• this should be added to the appfpga binary, and bootloader should be able to set the frequency using that.
• probably requires changes in the core qorc-sdk symbiflow toolchain, but perhaps we can use a post-processing script?