Add noatime to vfat and exfat

testNoAtime is new cts testcase, which verifies all writable
block filesystems are mounted "noatime" toavoid unnecessary
flash churn. So add noatime for vfat.

Bug: 64137815
Test: run cts -m m CtsOsTestCases -t android.os.cts.EnvironmentTest#testNoAtime
Change-Id: I4f42b54ed0d66e09964351da26d0d3bf38d573d6
1 file changed