Use only signed/unsigned numbers with ParseInt/ParseUint respectively

Test: build
Change-Id: I4d950d4aa8d24c90d1fc9b1cbea0f324aeed56a3
diff --git a/llkd/libllkd.cpp b/llkd/libllkd.cpp
index 58c2ba8..6840ed0 100644
--- a/llkd/libllkd.cpp
+++ b/llkd/libllkd.cpp
@@ -265,7 +265,7 @@
     }
     content.erase(pos);
     uid_t ret;
-    if (!android::base::ParseInt(content, &ret, uid_t(0))) {
+    if (!android::base::ParseUint(content, &ret, uid_t(0))) {
         return -1;
     }
     return ret;