Remove unused grantors function in MQDescriptor

We don't want to be returning a mutable reference to the grantors. Since
this function isn't being used anywhere, it is being removed.

Fixes: 162465295
Test: m && atest fmq_test
Change-Id: Ib5e519d100706c2443da99b85b27aa8dcb543d35
1 file changed