aarch64: Fix fma steering when rename fails [PR120119]

aarch64: Fix fma steering when rename fails [PR120119]

Regrename can fail in some case and `insn_rr[INSN_UID (insn)].op_info`
will be null. The FMA steering code was not expecting the failure to happen.
This started to happen after early RA was added but it has been a latent bug
before that.

Build and tested for aarch64-linux-gnu.

	PR target/120119

gcc/ChangeLog:

	* config/aarch64/cortex-a57-fma-steering.cc (func_fma_steering::analyze):
	Skip if renaming fails.

gcc/testsuite/ChangeLog:

	* g++.dg/torture/pr120119-1.C: New test.

Signed-off-by: Andrew Pinski <quic_apinski@quicinc.com>