udevadm: allow to override the default log level by environment variable

Previously, there was no way to override the log level for test and
test-builtin commands. Let's re-parse environment after setting the log
level to debug. Then, we can control the log level through environment
variable.

src/udev/udevadm-test-builtin.c

@@ -78,6 +78,7 @@ int builtin_main(int argc, char *argv[], void *userdata) {
         int r;
 
         log_set_max_level(LOG_DEBUG);
+        log_parse_environment();
 
         r = parse_argv(argc, argv);
         if (r <= 0)

src/udev/udevadm-test.c

@@ -95,6 +95,7 @@ int test_main(int argc, char *argv[], void *userdata) {
         int r;
 
         log_set_max_level(LOG_DEBUG);
+        log_parse_environment();
 
         r = parse_argv(argc, argv);
         if (r <= 0)