re PR other/69006 (Extraneous newline emitted between error messages in GCC 6)

re PR other/69006 (Extraneous newline emitted between error messages in GCC 6)

	PR other/69006
	PR testsuite/88920
	* lib/gcc-dg.exp: If llvm_binutils effective target, set
	allow_blank_lines to 2 during initialization.
	(dg-allow-blank-lines-in-output): Set allow_blank_lines to 1 only if
	it was previously zero.
	(gcc-dg-prune): Don't check for llvm_binutils effective target here.
	Clear allow_blank_lines afterwards whenever it was 1.
	* gdc.test/gdc-test.exp (dmd2dg): Don't call
	dg-allow-blank-lines-in-output here.
	(gdc-do-test): Set allow_blank_lines to 3 if it is 0 before running
	the tests and restore it back at the end.

From-SVN: r268930