X86: Use operator lookup for operator==, NFC

Avoid relying on the MachineInstrBundleIterator operator== being
implemented as a member function.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@278347 91177308-0d34-0410-b5e6-96231b3b80d8
1 file changed