binutils/testsuite: skip gentestdlls related tests if missing

When launching the testsuite through runtest outside the build tree,
gentestdlls might not be available, this binary being created by make
check.
Simply untested the related tests instead of crashing.

binutils/ChangeLog:

	* testsuite/binutils-all/objdump.exp: Skip dotnet tests if
	gentestdlls is not available.
1 file changed