Implement the #define variables required for synchronization: These
variables include offset and payload size values that vary from the Uu
interface, in relation to the PSS, SSS and PBCH elements. We also
introduce the new sl_mode command line flag, which is used to switch
between the Uu interface and SL interface. This will allow us to modify
exisitng PSS and SSS functions, without copying complete 5G functions
and only changing a few lines to support sidelink mode.

Fixing formatting for softmodem-common.h