Remove gdb-test-ivy-bridge.patch
    
    The patch 'gdb-test-ivy-bridge.patch' adds some disassembly tests for
    various i386/x86-64 instructions.  In fact, the tests added by this
    patch are copied directly from gas and should all be covered by
    gas/testsuite/gas/i386/i386.exp.
    
    I guess historically, when support for these instructions was first
    added, it made sense to have these tests in both GDB and binutils.
    But today I think that the testing in binutils is sufficient; if we
    really want to validate libopcodes we'd be better off building and
    testing gas/binutils as well as GDB.
    
    I propose that we just drop 'gdb-test-ivy-bridge.patch' from the
    Fedora GDB tree.