tree-optimization/111070 - fix ICE with recent ifcombine fix

We now got test coverage for non-SSA name bits so the following amends
the SSA_NAME_OCCURS_IN_ABNORMAL_PHI checks.

	PR tree-optimization/111070
	* tree-ssa-ifcombine.cc (ifcombine_ifandif): Check we have
	an SSA name before checking SSA_NAME_OCCURS_IN_ABNORMAL_PHI.

	* gcc.dg/pr111070.c: New testcase.

(cherry picked from commit 966b0a96)