fix library path for lexaloffle generator (#14525)

fixes #14511

Author: bryanforbes

package/batocera/core/batocera-configgen/configgen/configgen/generators/lexaloffle/lexaloffleGenerator.py

@@ -33,12 +33,12 @@ def getHotkeysContext(self) -> HotkeysContext:
 
     def generate(self, system, rom, playersControllers, metadata, guns, wheels, gameResolution):
         if (system.name == "pico8"):
-            LD_LIB="LD_LIBRARY_PATH=$LD_LIBRARY_PATH:"+str(BIOS / "pico-8")
+            LD_LIB=BIOS / "pico-8"
             BIN_PATH=PICO8_BIN_PATH
             CONTROLLERS=PICO8_CONTROLLERS
             ROOT_PATH=PICO8_ROOT_PATH
         elif (system.name == "voxatron"):
-            LD_LIB="LD_LIBRARY_PATH=$LD_LIBRARY_PATH:"+str(BIOS / "voxatron")
+            LD_LIB=BIOS / "voxatron"
             BIN_PATH=VOX_BIN_PATH
             CONTROLLERS=VOX_CONTROLLERS
             ROOT_PATH=VOX_ROOT_PATH
@@ -52,8 +52,7 @@ def generate(self, system, rom, playersControllers, metadata, guns, wheels, game
             raise BatoceraException(f"{BIN_PATH} is not set as executable")
 
         # the command to run
-        commandArray: list[str | Path] = [LD_LIB]
-        commandArray.extend([BIN_PATH])
+        commandArray: list[str | Path] = [BIN_PATH]
         commandArray.extend(["-desktop", SCREENSHOTS])  # screenshots
         commandArray.extend(["-windowed", "0"])                     # full screen
         # Display FPS
@@ -83,7 +82,11 @@ def generate(self, system, rom, playersControllers, metadata, guns, wheels, game
         with ensure_parents_and_open(CONTROLLERS, "w") as file:
                file.write(controllersconfig)
 
-        return Command.Command(array=commandArray, env={})
+        existing_library_path = os.environ.get("LD_LIBRARY_PATH")
+
+        return Command.Command(array=commandArray, env={
+            "LD_LIBRARY_PATH": f"{LD_LIB}:{existing_library_path}" if existing_library_path else LD_LIB
+        })
 
     def getInGameRatio(self, config, gameResolution, rom):
         return 4/3