RFE: Refactor lvm-dbus.c:call_lvm_method_sync()

[tbzatek]

As many said before, this function is gross and needs to be refactored.

Error: UNREACHABLE ([CWE-561](https://cwe.mitre.org/data/definitions/561.html)): [[#def6]](https://cov01.lab.eng.brq2.redhat.com/osh/task/285206/log/libblockdev-2.99-195.fc38/scan-results.html#def6)
libblockdev-2.99/src/plugins/lvm-dbus.c:887: unreachable: This code cannot be reached: "g_free(task_path);".
#  885|           return FALSE;
#  886|       }
#  887|->     g_free (task_path);
#  888|   
#  889|       return TRUE;

This is true, but the code is prone to mistakes once somebody makes any change and don't realize all the returns along the way.