Hi @shyams,
If you're a Canvas root account admin, I believe you could use custom CSS in your theme to accomplish this. The following code snippet should remove the Facebook link:
#footer-links a[href$="facebook.com/instructure"] {display: none;}
I would advise against removing the entire footer, as the Canvas acceptable use policy link lives there and could be considered very important for users.
Hope this helps!
-Chris
