Testsuite: GCN is always PIE.

Testsuite: GCN is always PIE.

The GCN/HSA loader ignores the load address and uses a random location, so we
build all GCN binaries as PIE, by default.

This patch makes the necessary testsuite adjustments to make this work
correctly.

2019-01-17  Andrew Stubbs  <ams@codesourcery.com>

	gcc/testsuite/
	* gcc.dg/graphite/scop-19.c: Check pie_enabled.
	* gcc.dg/pic-1.c: Disable on amdgcn.
	* gcc.dg/pic-2.c: Disable on amdgcn.
	* gcc.dg/pic-3.c: Disable on amdgcn.
	* gcc.dg/pic-4.c: Disable on amdgcn.
	* gcc.dg/pie-3.c: Disable on amdgcn.
	* gcc.dg/pie-4.c: Disable on amdgcn.
	* gcc.dg/uninit-19.c: Check pie_enabled.
	* lib/target-supports.exp (check_effective_target_pie): Add amdgcn.

From-SVN: r268026