[Trusty]Round up memory requested wrt. page size

Bug: 331234140

Change-Id: I9a33405a3e42846a7d00a274a301f69d9ba0fd7d
diff --git a/lib/sancov/sancov.c b/lib/sancov/sancov.c
index 6d8c2cb..80ece6e 100644
--- a/lib/sancov/sancov.c
+++ b/lib/sancov/sancov.c
@@ -107,7 +107,7 @@
     }
 
     req.hdr.cmd = COVERAGE_AGGREGATOR_CMD_REGISTER;
-    req.register_args.record_len = record_len(num_counters);
+    req.register_args.record_len = round_up(record_len(num_counters), PAGE_SIZE);
 
     rc = coverage_aggregator_rpc(chan, &req, NULL, &resp, &memref);
     if (rc != NO_ERROR) {