hw/pmod: change symbol library to local path

README.md

@@ -5,6 +5,7 @@
 ```
 hardware/ - Directory for any hardware designs
   pmod/ - A PMOD interface board, using 4 ADCs with LVDS converters to get data across PMOD
+  sonar_symbols.kicad_sym - custom KiCAD symbols I create for hardware
 ```
 
 ## Design Goals

hardware/pmod/sym-lib-table

@@ -1,3 +1,3 @@
 (sym_lib_table
-  (lib (name "Sonar")(type "KiCad")(uri "/home/david/ARVP/sonar_fpga/hardware/sonar_symbols.kicad_sym")(options "")(descr ""))
+  (lib (name "Sonar")(type "KiCad")(uri "${KIPRJMOD}/../sonar_symbols.kicad_sym")(options "")(descr ""))
 )