You can also remove manually following bellow steps:

1. Login to your Odoo application as an Admin.
2. Activate the Technical Settings (Developer Mode) by going to Settings->Activate the developer mode.
3. Then under the User Interface option, select the Views.
4. Search for Brand Promotion Message. Click to open and then say Edit.
5. Just Remove or Comment line no. 2 to 8.

Hi,

The text "Powered By Odd" is a branding that generating from a template. To remove that First enable debug mode from settings, Then got Settings -> Technical -> User Interface -> Views

Search for "bran" in it. Then you can see different template  for branding.From that select the "Brand Promotion Message " Template

And then just command the code inside the template

By doing this , The "Powered By Odoo " will not be visible in the login page.

The branding is removed from login page

Hope it helps