Add isSystem to Location Op dumpsys logging

Also guard the logging with LOCATION_OPS check which was missing
previously.

Example logs:
    09-10 13:40:29.602 I PrivacyLog: Location Op: com.google.android.gms(10146) importance=125 isFg=true isSystem=true
    09-10 13:40:31.219 I PrivacyLog: Location Op: com.google.android.apps.maps(10209) importance=100 isFg=true isSystem=false
    09-10 13:40:35.996 I PrivacyLog: Location Op: com.google.android.apps.location.flpdebugger(10153) importance=100 isFg=true isSystem=false
    09-10 13:40:39.594 I PrivacyLog: Location Op: com.google.android.gms(10146) importance=100 isFg=true isSystem=true
    09-10 13:40:44.664 I PrivacyLog: Location Op: com.google.android.apps.maps(10209) importance=400 isFg=false isSystem=false
    09-10 13:40:46.021 I PrivacyLog: Location Op: com.google.android.apps.location.flpdebugger(10153) importance=100 isFg=true isSystem=false
    09-10 13:40:56.302 I PrivacyLog: Location Op: com.google.android.GoogleCamera(10138) importance=100 isFg=true isSystem=false

Bug: 440396862
Test: on device
Flag: EXEMPT logging only
Change-Id: I707cd85a15f250a71d4df3de90220e87b0422a2e