how to flash CC2530 without cc debugger?
It is possible to make a flash bootloader in the CC2530 - so that it will update its own flash with a program received over the USB link (or even by over the air).  

But the CC2530 is not supplied with a Bootloader installed - so the first time you program the device you will need the CC debugger. 

If you want to make your own version of the CC debugger that is also possible, the protocol is detailed here:

http://www.ti.com/lit/ug/swra124/swra124.pdf