compile iNav firmware using cmake

The iNav repo: https://github.com/iNavFlight/inav
Must use version 5.
Target : MATEKF411SE.
You must change these things :
change in vtx_smartaudio.c:

const char * saPowerNames[VTX_SMARTAUDIO_MAX_POWER_COUNT + 1] = {
"----", "250 ", "500 ", "1000", "2000", "3000"
};

// Fill table with standard values for SA 1.0 and 2.0
saPowerTable_t saPowerTable[VTX_SMARTAUDIO_MAX_POWER_COUNT] = {
{ 250, 7 },
{ 500, 16 },
{ 1000, 25 },
{ 2000, 40 },
{ 3000, 80 }
};

And change in vtx_smartaudio.h:

#define VTX_SMARTAUDIO_DEFAULT_POWER_COUNT 5