No error message thrown when wrong value is passed to "--sort-column" argument.

No error message thrown when wrong value is passed to "--sort-column" argument.
--sort-column is an argument used for sorting the output of "openstack resource provider usage show" command on the basis of specified column. If we provide invalid column name in command then also it shows output without any error message.

Reproducing steps:
1. By default output of show command:

[root@queens1 ~(keystone_admin)]# openstack resource provider usage show d04d9b87-4bff-47d8-a4ca-06deadcb6f80
+----------------+-------+
| resource_class | usage |
+----------------+-------+
| VCPU | 4 |
| MEMORY_MB | 2048 |
| DISK_GB | 5 |
+----------------+-------+

2. Sorting is done on the basis of "usage" column

[root@queens1 ~(keystone_admin)]# openstack resource provider usage show --sort-column usage d04d9b87-4bff-47d8-a4ca-06deadcb6f80
+----------------+-------+
| resource_class | usage |
+----------------+-------+
| VCPU | 4 |
| DISK_GB | 5 |
| MEMORY_MB | 2048 |
+----------------+-------+

3. Now wrong value is passed in --sort-column argument and same output is visible. however, it must throw some error message.

[root@queens1 ~(keystone_admin)]# openstack resource provider usage show --sort-column DISK_GB d04d9b87-4bff-47d8-a4ca-06deadcb6f80
+----------------+-------+
| resource_class | usage |
+----------------+-------+
| VCPU | 4 |
| MEMORY_MB | 2048 |
| DISK_GB | 5 |
+----------------+-------+

Ideally, command in step no. 3 must generate an error "Invalid value passed in --sort-column argument".