Yes the stm32f205 and 207 ld files are same because they share the same memory mapping. If your specific hardware requires changes please modify the ld files as appropriate to your hardware.
For your specific board, please add your board definitions to .../platforms directory. You may copy the .../platforms/BCM943362WCD4 as reference and change the GPIO and peripheral mapping according to your custom board. Change the STM32F2x5 to STM32F2x7 to point to correct ld files.