refactor: clock for AXI buses is from PL osc, add reset tree conf
It seems much stable to provide clocks from a stable source for the whole AXI tree. Added optional reset tree configuration options. Config(RESET_MODE) Reset tree option:
- PS: reset AXI tree using PS FCLK_RESET0_N pin, PCIe reset connected to IO
- PCIE: reset AXI tree using pcie_rst_n signal, PCIe reset connected to IO
- PS_PCIE: reset AXI tree and PCIe using PS FCLK_RESET0_N pin