Added additional comments for vendor error codes

Added documentation for vendor code of 0 as well as changing the value
of vendor codes to be from 0x0001 to 0xffff

Bug: 268748245
Test: manual
Change-Id: I355524acc0094bbf3ecd5183df77cbeea82d55b1
diff --git a/automotive/vehicle/aidl/android/hardware/automotive/vehicle/StatusCode.aidl b/automotive/vehicle/aidl/android/hardware/automotive/vehicle/StatusCode.aidl
index 029b2ac..fd4b199 100644
--- a/automotive/vehicle/aidl/android/hardware/automotive/vehicle/StatusCode.aidl
+++ b/automotive/vehicle/aidl/android/hardware/automotive/vehicle/StatusCode.aidl
@@ -18,8 +18,9 @@
 
 /**
  * Error codes used in vehicle HAL interface. System defined error codes will have the range from
- * 0x00000000 to 0x0000ffff and vendor error codes will have the range from 0x0000 << 16 to
- * 0xffff << 16. The error code is formatted as [VENDOR_ERROR] << 16 | [SYSTEM_ERROR]
+ * 0x0000 to 0xffff and vendor error codes will have the range from 0x0001 to 0xffff. The error code
+ * is formatted as [VENDOR_ERROR] << 16 | [SYSTEM_ERROR]. A vendor error code of 0 indicates vendor
+ * code not set.
  */
 @VintfStability
 @Backing(type="int")