Add -ffuse-ops-with-volatile-access: Adjust 'gcc.target/nvptx/alloca-5.c' [PR122343]

Add -ffuse-ops-with-volatile-access: Adjust 'gcc.target/nvptx/alloca-5.c' [PR122343]

With commit r16-5947-ga6c50ec2c6ebcbda2b032eee0552a6a486355e12
"Add -ffuse-ops-with-volatile-access", GCC/nvptx avoids use of intermediate
registers in applicable cases (nice!).  This causes one test suite regression:

    PASS: gcc.target/nvptx/alloca-5.c (test for excess errors)
    XFAIL: gcc.target/nvptx/alloca-5.c execution test
    [-PASS:-]{+FAIL:+} gcc.target/nvptx/alloca-5.c check-function-bodies f
    PASS: gcc.target/nvptx/alloca-5.c check-function-bodies g

Adjust the FAILing 'check-function-bodies' as per the improved code generation.

	PR target/122343
	gcc/testsuite/
	* gcc.target/nvptx/alloca-5.c: Adjust.