Adjust 'libgomp.c++/target-exceptions-pr118794-1.C' for 'targetm.arm_eabi_unwinder...

Adjust 'libgomp.c++/target-exceptions-pr118794-1.C' for 'targetm.arm_eabi_unwinder' [PR118794]

Fix-up for commit aa3e72f943032e5f074b2bd2fd06d130dda8760b
"Add test cases for exception handling constructs in dead code for GCN, nvptx target and OpenMP 'target' offloading [PR118794]":
we need to adjust for configurations with 'targetm.arm_eabi_unwinder', as per:

    gcc/config/arm/arm.cc:#define TARGET_ARM_EABI_UNWINDER true
    gcc/config/c6x/c6x.cc:#define TARGET_ARM_EABI_UNWINDER true

..., which for ARM is conditional to '#if ARM_UNWIND_INFO' (defined in
'gcc/config/arm/bpabi.h', used for various GCC configurations), and for
C6x unconditional.

This gets us:

    --- target-exceptions-pr118794-1.C.269t.optimized
    +++ target-exceptions-pr118794-1.C.270t.optimized
    [...]
     __attribute__((omp declare target))
     void f ()
    [...]
       gimple_call <__dt_comp , NULL, &c>
    -  gimple_call <__builtin_eh_pointer, _7, 2>
    -  gimple_call <__builtin_unwind_resume, NULL, _7>
    +  gimple_call <__builtin_cxa_end_cleanup, NULL>

     }
    [...]

	PR target/118794
	libgomp/
	* testsuite/libgomp.c++/target-exceptions-pr118794-1.C: Adjust for
	'targetm.arm_eabi_unwinder'.
	* testsuite/libgomp.c++/target-exceptions-pr118794-1-offload-sorry-GCN.C:
	Likewise.
	* testsuite/libgomp.c++/target-exceptions-pr118794-1-offload-sorry-nvptx.C:
	Likewise.