presence of rvtest_strap_routine must be conditional on presence of smode (issue #552)

[allenjbaum]

riscv-arch-test/riscv-test-suite/rv32i_m/pmp32/src/pmp-CFG-reg.S

Line 39 in cd94912

RVTEST_CASE(1,"//check ISA:=regex(.*32.*); check ISA:=regex(.*I.*S.*Zicsr.*); def rvtest_mtrap_routine=True; def rvtest_strap_routine=True; def TEST_CASE_1=True; mac PMP_MACROS; mac PMP_helper_Coverpoints",pmp_cfg_locked_write_unrelated)

This should still compile if smode isn't present, but rvtest_strap_routine must not be defined in that case, because it will try to touch nonexistent CSRs, so either this must be a separate instantiation of the RVTEST_CASE macro
or possibly a conditional assignment:
?maybe something like? RVTEST_CASE(1,"//check ISA:=regex(.32.); check ISA:=regex(.*I.Zicsr.); def rvtest_mtrap_routine=True; def TEST_CASE_1=True; def rvtest_strap_routine = check ISA:=regex(.S.);mac PMP_MACROS; mac PMP_helper_Coverpoints",pmp_cfg_locked_write_unrelated;)