Remove calls to is_selinux_enabled()

d34e407aeb5898f19d4f042b7558420bbb3a1817 removed support for
running with SELinux completely disabled. SELinux must either be
in permissive or enforcing mode now.

Remove unnecessary calls to is_selinux_enabled(). It always returns
true now.

Change-Id: Ife3156b74b13b2e590afe4accf716fc7776567e5
diff --git a/daemon/main.cpp b/daemon/main.cpp
index 78ab3f6..d7fa362 100644
--- a/daemon/main.cpp
+++ b/daemon/main.cpp
@@ -171,7 +171,7 @@
 
         D("Local port disabled\n");
     } else {
-        if ((root_seclabel != nullptr) && (is_selinux_enabled() > 0)) {
+        if (root_seclabel != nullptr) {
             if (setcon(root_seclabel) < 0) {
                 LOG(FATAL) << "Could not set selinux context";
             }