platforms/limesdr_mini_v2.py: fixed SPI Flash pinout MOSI <-> MISO

Author: trabucayre

litex_boards/platforms/limesdr_mini_v2.py

@@ -37,8 +37,8 @@
     ("spiflash", 0,
         Subsignal("cs_n", Pins("U17")),
         Subsignal("clk",  Pins("U16")),
-        Subsignal("miso", Pins("U18")),
-        Subsignal("mosi", Pins("T18")),
+        Subsignal("miso", Pins("T18")),
+        Subsignal("mosi", Pins("U18")),
         IOStandard("LVCMOS33"),
     ),