fix scan-build issues

The static analyzer scan-build had a few issues with analysing
parts of systemd.

gpt-auto-generator.c:
scan-build could not find blkid.h. Whether it should be blkid.h or
blkid/blkid.h seems to depend on the version used. We already use
blkid/blkid.h in udev-builtin-blkid.c so it seems safe to use that
here too.

Makefile.am:
Moved some -D's from CFLAGS to CPPFLAGS. I also simplified them a
bit and got rid of a left over DBUS_CFLAGS.

test-cgroup-mask.c/test-sched-prio.c
A variable was added to store the replaced TEST_DIR. When wrapped
in an assert_se TEST_DIR was not replaced in the logged error.
While not an issue introduced in this patch we might as well fix
it up while we are here.

2 files changed, 4 insertions, 2 deletions

diff --git a/src/test/test-cgroup-mask.c b/src/test/test-cgroup-mask.c
index 0f145d6bc4..99c8ceea76 100644
--- a/src/test/test-cgroup-mask.c
+++ b/src/test/test-cgroup-mask.c
@@ -37,9 +37,10 @@ static int test_cgroup_mask(void) {
         FILE *serial = NULL;
         FDSet *fdset = NULL;
         int r;
+        const char *dir = TEST_DIR;
 
         /* Prepare the manager. */
-        assert_se(set_unit_path(TEST_DIR) >= 0);
+        assert_se(set_unit_path(dir) >= 0);
         r = manager_new(SYSTEMD_USER, &m);
         if (r == -EPERM || r == -EACCES) {
                 puts("manager_new: Permission denied. Skipping test.");
diff --git a/src/test/test-sched-prio.c b/src/test/test-sched-prio.c
index 56e11f8daf..a4cc3d44a2 100644
--- a/src/test/test-sched-prio.c
+++ b/src/test/test-sched-prio.c
@@ -31,9 +31,10 @@ int main(int argc, char *argv[]) {
         FILE *serial = NULL;
         FDSet *fdset = NULL;
         int r;
+        const char *dir = TEST_DIR;
 
         /* prepare the test */
-        assert_se(set_unit_path(TEST_DIR) >= 0);
+        assert_se(set_unit_path(dir) >= 0);
         r = manager_new(SYSTEMD_USER, &m);
         if (r == -EPERM || r == -EACCES || r == -EADDRINUSE || r == -EHOSTDOWN) {
                 printf("Skipping test: manager_new: %s", strerror(-r));