SELinuxHostTest: Fix testValidServiceContexts()

Test method testValidServiceContexts() should run checkfc with the
service_contexts file to ensure that they are valid. Currently,
it's using the property_contexts file. Update the test to use
service_contexts.

Change-Id: Id8eede43d73bb480e34c52107d7132a0cd626ceb
Signed-off-by: William Roberts <william.c.roberts@intel.com>
1 file changed