analog_pocket: Add Serial (to fix CI) and add to board list.

README.md

@@ -99,6 +99,7 @@ Some of the suported boards, see yours? Give LiteX-Boards a try!
     ├── aliexpress_xc7k420t
     ├── alinx_ax7010
     ├── alinx_axu2cga
+    ├── analog_pocket
     ├── antmicro_artix_dc_scm
     ├── antmicro_datacenter_ddr4_test_board
     ├── antmicro_lpddr4_test_board

litex_boards/platforms/analog_pocket.py

@@ -15,6 +15,13 @@ _io_physical_litex = [
     ("clk74a", 0, Pins("V15"), IOStandard("3.3-V LVCMOS")),
     ("clk74b", 0, Pins("H16"), IOStandard("1.8 V")),
 
+    # Serial.
+    ("serial", 0,
+        Subsignal("tx", Pins("K21")),
+        Subsignal("rx", Pins("K22")),
+        IOStandard("1.8V")
+    ),
+
     # SDR SDRAM
     ("sdram_clock", 0, Pins("G12"), IOStandard("1.8V")),
     ("sdram", 0,