re PR testsuite/18338 (mmix-knuth-mmixware testsuite failure: gcc.dg/bitfld-4.c and g++.dg/abi/bitfield4.C)

	PR target/18338
	* gcc.dg/bitfld-4.c, g++.dg/abi/bitfield4.C: Gate on
	pcc_bitfield_type_matters || default_packed.

From-SVN: r106377