Add IOKit linker args for macOS, disable errors as warnings for all p…

…latforms

Due to the serial driver, macOS will not compile this project due to lack of linking to IOKit. This is now fixed, but the serial driver is deprecated so this change is largely meaningless.

Disabled reporting warnings as errors to avoid build jobs failing due to warnings.

build.gradle

@@ -78,6 +78,9 @@ model {
         }
       }
       binaries.all {
+        if (it.targetPlatform.name == 'osxuniversal') {
+          linker.args '-framework', 'IOKit'
+        }
         if (it.targetPlatform.name == nativeUtils.wpi.platforms.roborio) {
           it.buildable = false
         }

config.gradle

@@ -14,7 +14,6 @@ nativeUtils {
 }
 
 nativeUtils.wpi.addWarnings()
-nativeUtils.wpi.addWarningsAsErrors()
 
 nativeUtils.setSinglePrintPerPlatform()